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中文联络人: 牟志坚

金融学 Finance and capital markets

对冲基金很坏吗 Are Hedge Funds Bad 对冲基金结构和收费 Hedge Fund Structure and Fees 交易所交易基金(ETF) Exchange Traded Funds (ETFs) 封闭式共同基金 Closed-End Mutual Funds 房价上涨谜团第2部分 Housing price conundrum (part 2) 开放式共同基金赎回 Open-End Mutual Fund Redemptions 开放式共同基金(部分1) Open-Ended Mutual Fund (Part 1) 有限责任和重复征税是否公平 Is Limited Liability or Double Taxation Fair 公司和有限责任 Corporations and Limited Liability 办公室租用粗略计算 Back of Envelope Office Space Conundrum 定期寿险和死亡概率 Term Life Insurance and Death Probability 替代性最低税 Alternative Minimum Tax 税款减免简介 Tax Deductions Introduction 公允价值会计 Fair Value Accounting 伦敦银行同业拆放利率 LIBOR 资本结构差异基础 Basic Capital Structure Differences 摊销和折旧 Amortization and Depreciation 现金流中考虑折旧 Depreciation in Cash Flow 卡车折旧 Depreciating the truck 卡车成本导致经营业绩不一致 Expensing a Truck leads to inconsistent performance 应付账款增加的例子 Doing the example with Accounts Payable growing 资产负债表和损益表关系 Balance Sheet and Income Statement Relationship 租房和买房(细节分析) Renting vs. Buying (detailed analysis) 权责发生制和收付实现制会计对比 Comparing Accrual and Cash Accounting 权责发生制会计 Accrual Basis of Accounting 收付实现制会计 Cash Accounting 期货合约套利II Arbitraging Futures Contracts II 期货合约套利 Arbitraging Futures Contract 远期结算价格下限 Lower Bound on Forward Settlement Price 远期结算价格上限 Upper Bound on Forward Settlement Price 期货溢价和现货溢价回顾 Contango and Backwardation Review 现货溢价 Backwardation 期货溢价 Contango 租房和买房对比第2部分 Renting vs. buying a home (part 2) 期货和远期曲线 Futures and Forward Curves 期货保证金机制验证 Verifying Hedge with Futures Margin Mechanics 期货保证金机制 Futures Margin Mechanics 货交易的动机 Motivation for the Futures Exchange 期货介绍 Futures Introduction 远期合约介绍 Forward Contract Introduction 租房和买房 Renting vs. Buying a home 现值2 Present Value 2 现值1 Introduction to Present Value 利息2 Interest (part 2) 利息介绍 Introduction to interest

货币银行学 Banking and money

Python编程 Python Programming

微观经济学 Microeconomics

欧洲和美国历史 European and US history

算术和代数预备:算术的性质 Arithmetic and pre-algebra: Arithmetic properties

有机化学 Organic Chemistry

有机物的命名例题3 More Organic Chemistry Naming Examples 3 有机物的命名例题1 More Organic Chemistry Naming Examples 1 更正:2-丙基庚烷不叫这个名字! Correction-2-Propylheptane should never be the name 烯烃的顺反和E-Z命名 Cis-Trans and E-Z Naming Scheme for Alkenes 卤代烃的命名 Naming Alkyl Halides 羟醛反应 Aldol Reaction 酰氯的胺化 Amide Formation from Acyl Chloride 羧酸衍生物的稳定性 Relative Stability of Amides Esters Anhydrides and Acyl Chlorides 酰胺、酸酐、酯和酰氯 Amides, Anhydrides, Esters and Acyl Chlorides 酰氯的形成 Acid Chloride Formation 费舍尔酯化反应 Fisher Esterification 羧酸的命名 Carboxylic Acid Naming 羧酸的简介 Carboxlic Acid Introduction 烯醇-酮互变异构 Keto Enol Tautomerization Sn2反应中的胺的亲核作用 Amine as Nucleophile in Sn2 Reaction 胺的命名2 Amine Naming 胺的命名简介 Amine Naming Introduction 苯的溴化 Bromination of Benzene 芳香烃的亲电取代反应 Electrophilic Aromatic Substitution 简单的苯的衍生物的命名 Naming Benzene Derivatives Introduction 芳香性与休克尔定律 Aromatic Compounds and Huckel's Rule 环醚的SN2和SN1开环反应 Sn1 and Sn2 epoxide opening discussion 环醚的SN2开环反应 Ring-opening Sn2 reaction of expoxides 环醚的命 Cyclic ethers and epoxide naming 醚的简介和命名 Ether Naming and Introduction 醇的性质 Alcohol Properties 醇 Alcohols 自由基反应 Free Radical Reactions E1、E2、SN1、SN2反应例题3 E2 E1 Sn2 Sn1 Reactions Example 3 E2、E1、SN2、SN1反应例题2 E2 E1 Sn2 Sn1 Reactions Example 2 E1反应 E1 Reactions E2反应 E2 Reactions 亲核性 Nucleophilicity (Nucleophile Strength) 溶剂对SN1和SN2反应的影响 Solvent Effects on Sn1 and Sn2 Reactions 酸催化加成反应 Addition of Water (Acid-Catalyzed) Mechanism 甲基环己烷的纽曼式 Double Newman Diagram for Methcyclohexane 纽曼投影式 Newman Projections sp3杂化轨道与σ键 sp3 Hybridized Orbitals and Sigma Bonds 弗氏酰基化反应补充 Friedel Crafts Acylation Addendum 弗氏酰基化反应 Friedel Crafts Acylation 酮的命名 Ketone Naming 醛的简介 Aldehyde Introduction Sn1反应中的胺 Sn1 Amine Reaction Sn2反应中的胺的亲核作用2 Amine in Sn2 part 苯的共振 Resonanc 比较E2,E1,SN2,SN1等四种反应 Comparing E2 E1 Sn2 Sn1Reaction 扎伊采夫规则 Zaitsev's Rule 异、仲、叔碳支链的习惯命名和系统命名

微分方程 Differential equations

恰当方程2 Exact Equations Intuition 2 卷积导论 Introduction to the Convolution 可分离变量微分方程2 Separable differential equations 2 拉普拉斯变换2 Laplace Transform 2 拉普拉斯变换1 Laplace Transform 1 待定系数法4 Undetermined Coefficients 4 待定系数法2 Undetermined Coefficients 2 待定系数法1 Undetermined Coefficients 1 特征方程的重根2 Repeated roots of the characteristic equations 2 特征方程的复根3 Complex roots of the characteristic equations 3 特征方程的复根2 Complex roots of the characteristic equations 2 特征方程的复根1 Complex roots of the characteristic equations 1 二阶线性齐次微分方程4 2nd Order Linear Homogeneous Differential Equations 4 二阶线性齐次微分方程3 2nd Order Linear Homogeneous Differential Equations 3 二阶线性齐次微分方程2 2nd Order Linear Homogeneous Differential Equations 2 一阶齐次方程1 First order homegenous equations 1 利用卷积定理求解初值问题 Using the Convolution Theorem to Solve an Initial Value Problem 卷积和拉普拉斯变换 The Convolution and the Laplace Transform 狄拉克δ函数的拉普拉斯变换 Laplace Transform of the Dirac Delta Function 狄拉克δ函数 Dirac Delta Function 带有单位阶梯函数的微分方程 Laplace-Step Function Differential Equation 拉普拉斯逆变换的一些例子 Inverse Laplace Examples 单位阶跃函数的拉普拉斯变换 Laplace Transform of the Unit Step Function t^n的拉普拉斯变换 Laplace Transform of t^n: L{t^n} t的拉普拉斯变换 Laplace Transform of t: L{t} 用拉式变换解非齐次方程 Using the Laplace Transform to solve a nonhomogenous equation 更多的拉式变换性质 More Laplace Transform tools

对数 Logarithms

代数习题课 Algebraic Practice Problem

通过平方根解二次方程 Solving Quadratic Equations by Square Roots 通过画图解二次方程 Solving Quadratic Equations by Graphing 二次函数的图形 Graphs of Quadratic Functions 分组分解多项式 Factor by Grouping and Factoring Completely 分解特殊的二次多项式 Factoring Special Products 分解二次多项式 Factoring Quadratic Expressions 多项式方程的分解形式 Polynomial Equations in Factored Form 特殊的二项式乘法 Special Products of Binomials 多项式乘法 Multiplication of Polynomials 多项式加减法 Addition and Subtraction of Polynomials 指数增长和衰减的应用题 Word Problem Solving- Exponential Growth and Decay 等比数列介绍 Geometric Sequences (Introduction) 指数衰减函数 Exponential Decay Functions 指数增长函数 Exponential Growth Functions 科学计数法 Scientific Notation 零,负和分数指数 Zero, Negative, and Fractional Exponents 商的指数性质 Exponent Properties Involving Quotients 乘积的指数性质 Exponent Properties Involving Products 线性不等式组 Systems of Linear Inequalities 线性方程组的特殊形 Special Types of Linear Systems 用乘法解方程组 Solving Systems of Equations by Multiplication 用消除法解方程组 Solving Systems of Equations by Elimination 用替代法解线性方程组n Solving Linear Systems by Substitution 用画图法解线性方程组 Solving Linear Systems by Graphing 不等式图像 Graphing Inequalities 绝对值不等式 Absolute Value Inequalities 绝对值方程 Absolute Value Equations 复合不等式 Compound Inequalities 多步不等式 Multi-Step Inequalities 乘除不等式 Inequalities Using Multiplication and Division 加减不等式 Inequalities Using Addition and Subtraction 线性模型的使用 Using a Linear Model 用线性模型做预测 Predicting with Linear Models 对数据做线性处理 Fitting a Line to Data 平行线和垂线方 Equations of Parallel and Perpendicular Lines 线性方程的标准形式 Linear Equations in Standard Form 线性方程的点斜式 Linear Equations in Point Slope Form 线性方程的斜截式 Linear Equations in Slope Intercept Form 解应用题 Word Problem Solving 4 函数例题-线性函数图 Function Example Problem-Linear Function Graphs 两边都有变量的方程 Equations with Variables on Both Sides 平方根与实数 Square Roots and Real Numbers

算术与代数预备:乘除 Arithmetic and Pre-Algebra Multiplication-Division

微积分预备 Precalculus

SAT数学 SAT Math

SAT测试5第3部分1 SAT Prep- Test 5 Section 3 Part 1 SAT测试4第8部分1 SAT Prep- Test 4 Section 8 Part 1 SAT测试4第4部分3 SAT Prep- Test 4 Section 4 Part 3 SAT测试4第4部分1 SAT Prep- Test 4 Section 4 Part 1 SAT测试4第2部分6 SAT Prep- Test 4 Section 2 Part 6 SAT测试4第2部分5 SAT Prep- Test 4 Section 2 Part 5 SAT测试4第2部分4 SAT Prep- Test 4 Section 2 Part 4 SAT测试4第2部分3 SAT Prep- Test 4 Section 2 Part 3 SAT测试4第2部分1 SAT Prep- Test 4 Section 2 Part 1 SAT测试3第8部分4 SAT Prep- Test 3 Section 8 Part 4 SAT测试3第8部分2 SAT Prep- Test 3 Section 8 Part 2 SAT测试3第8部分1 SAT Prep- Test 3 Section 8 Part 1 SAT测试3第4部分4 SAT Prep- Test 3 Section 4 Part 4 SAT测试3第4部分3 SAT Prep- Test 3 Section 4 Part 3 SAT测试3第4部分2 SAT Prep- Test 3 Section 4 Part 2 SAT测试3第4部分1 SAT Prep- Test 3 Section 4 Part 1 SAT测试2第9部分3 SAT Prep- Test 2 Section 9 Part 3 SAT测试2第9部分2 SAT Prep- Test 2 Section 9 Part 2 SAT测试2第9部分1 SAT Prep- Test 2 Section 9 Part 1 SAT测试2第6部分6 SAT Prep- Test 2 Section 6 Part 6 SAT测试2第6部分5 SAT Prep- Test 2 Section 6 Part 5 SAT测试2第6部分3 SAT Prep- Test 2 Section 6 Part 3 SAT测试2第6部分1 SAT Prep- Test 2 Section 6 Part 1 SAT测试2第3部分5 SAT Prep- Test 2 Section 3 part 5 SAT测试5第7部分6 SAT Prep- Test 5 Section 7 Part 6 SAT测试5第7部分5 SAT Prep- Test 5 Section 7 Part 5 SAT测试5第7部分4 SAT Prep- Test 5 Section 7 Part 4 SAT测试5第7部分3 SAT Prep- Test 5 Section 7 Part 3 SAT测试5第7部分2 SAT Prep- Test 5 Section 7 Part 2 SAT测试5第7部分1 SAT Prep- Test 5 Section 7 Part 1 SAT测试5第3部分6 SAT Prep- Test 5 Section 3 Part 6 SAT测试5第3部分5 SAT Prep- Test 5 Section 3 Part 5 SAT测试5第3部分4 SAT Prep- Test 5 Section 3 Part 4 SAT测试5第3部分3 SAT Prep- Test 5 Section 3 Part 3 SAT测试1第3部分6 SAT Prep- Test 1 Section 3 Part 6 SAT测试3第2部分5 SAT Prep- Test 3 Section 2 Part 5 SAT测试3第2部分4 SAT Prep- Test 3 Section 2 Part 4 SAT测试3第2部分3 SAT Prep- Test 3 Section 2 Part 3 SAT测试3第2部分2 SAT Prep- Test 3 Section 2 Part 2 SAT测试3第2部分1 SAT Prep- Test 3 Section 2 Part 1

几何学-角

角平分线定理的证明 Angle Bisector Theorem Proof 角平分线定理 Angle Bisector Theorem Examples 三角形的角例3 Triangle Angle Example 3 平行线形成的角2 Angles of parallel lines 2 证明同位角相等则直线平行 Proof - Corresponding Angle Equivalence Implies Parallel Lines 平行线与截线形成的角 Angles formed between transversals and parallel lines 角3 Angles (part 3) 证明 互为对顶角的两角相等 Proof-Vertical Angles are Equal 角2 Angles (part 2) 找出余角和补角 Identifying Complementary and Supplementary Angles 余角和补角 Complementary and Supplementary Angles 锐角 钝角和直角 Acute Obtuse and Right Angles 锐角 直角 和钝角 Acute Right and Obtuse Angles 测量角度 Measuring Angles 使用量角器 Using a Protractor 角的测量——角度制 Measuring Angles in Degrees 角的简介 Introduction to angles (old) 角的定义 Angle basics 圆周角和圆心角 Inscribed and Central Angles 利用两栏证明法证明线段相互垂直 Two column proof showing segments are perpendicular 点到直线的距离及角平分线 Point Line Distance and Angle Bisectors 平行线与截线形成的角 Two column proof showing segments are perpendicular 边边角不一定成立的原因 More on why SSA is not a postulate 角的游戏2 The Angle Game 2 角的游戏 The Angle Game 三角形的角例2 Triangle Angle Example 2 三角形的角例1 Triangle Angle Example 1 证明 三角形内角和为180度 Proof - Sum of Measures of Angles in a Triangle are 180 两线相交构成的角 Introduction to vertical angles 求更多未知角 Finding more angles 求未知角 Finding Missing Angles

线性代数 Linear Algebra

左零空间和行空间的可视化 Visualizations of Left Nullspace and Rowspace 行空间和左零空间 Rowspace and Left Nullspace 向量的转置 Transpose of a Vector 转置矩阵的加法与求逆运算 Transposes of sums and inverses 矩阵乘积的转置 Transpose of a Matrix Product 转置的行列式 Determinant of Transpose 矩阵的转置 Transpose of a Matrix 行列式作为面积因子 Determinant as Scaling Factor 行列式与平行四边形面积 Determinant and area of a parallelogram 奇异矩阵 Singular Matrices 行列式的简化 Simpler 4×4 determinant 4×4 上三角阵行列式 Upper Triangular Determinant 行变换后的行列式 Determinant after row operations 有相同行的行列式 Duplicate Row Determinant 行相加的矩阵行列式规律 Determinant when row is added 关于行乘系数行列式的修正 (correction)scalar multiplication of row 矩阵行乘以系数的行列式运算 Determinant when row multiplied by scalar 法则 Rule of Sarrus of Determinants Sarrus 沿其他行或列求矩阵行列式 Determinants along other rows-columns 矩阵法求向量组合 Matrices to solve a vector combination problem 3×3矩阵的行列式 3×3 Determinant 矩阵的逆矩阵一般形式 Formula for 2×2 inverse 2×2 求逆矩阵举例 Example of Finding Matrix Inverse 求逆矩阵的方法 Deriving a method for determining inverses 展示逆是线性的 Showing that Inverses are Linear 可逆性的简化条件 Simplifying conditions for invertibility 矩阵进行1-1变换的条件 Matrix condition for one-to-one transformation 探索Ax=b的解答集合 Exploring the solution set of Ax=b 映上变换的判别方法 Determining whether a transformation is onto 矩阵法求解方程组 Matrices to solve a system of equations 满射函数和单射函数 Surjective (onto) and Injective (one-to-one) functions 逆函数介绍 Linear Algebra- Introduction to the inverse of a function 矩阵乘法分配律 Distributive Property of Matrix Products 矩阵乘法结合律 Matrix Product Associativity 矩阵乘积范例 Linear Algebra Matrix Product Examples 线性变换的复合2 Compositions of Linear Transformations 2 线性变换的复合1 Compositions of Linear Transformations 1 投影介绍 Introduction to Projections 矩阵的逆(三) Inverting Matrices (part3) 单位向量 Unit Vectors 在R3空间内做旋转 Rotation in R3 around the X-axis 在R2空间的线性变换的旋转举例 Linear Transformation Examples Rotations in R2 线性变换的例子——放缩和映射 Linear Transformation Examples- Scaling and Reflections 矩阵加法和标量乘法详细论述 More on Matrix Addition and Scalar Multiplication 集合的原像 Preimage of a set 变换下的子集原像 Image of a subset under a transformation 矩阵的逆(二) Inverting Matrices(part 2) 矩阵的逆(一) Idea Behind Inverting a 2x2 Matrix 零空间1-矩阵零空间介绍 Null Space 1- Introduction to the Null Space of a Matrix 矩阵向量乘积 Matrix Vector Products 矩阵行简化阶梯型3 Matrices- Reduced Row Echelon Form 3 矩阵行简化阶梯型2 Matrices- Reduced Row Echelon Form 2 矩阵行简化阶梯型1 Matrices- Reduced Row Echelon Form 1 矩阵乘法(二) Matrix multiplication (part 2) 乘和叉乘的直觉比较 Dot and Cross Product Comparison-Intuition 外积简介 Cross Product Introduction 中由点与法向量定义的平面 Defining a plane in R3 with a point and normal vector 向量夹角的定义 Defining the angle between vectors 向量三角不等式 Linear Algebra- Vector Triangle Inequality 柯西许瓦兹不等式的证明 Proof of the Cauchy-Schwarz Inequality 向量点积的性质及证明 Proving Vector Dot Product Properties 向量的点积和模长 Vector Dot Product and Vector Length 线性代数——子空间的基 Linear Algebra-Basis of a Subspace 矩阵乘法(一) Matrix multiplication (part 1) 线性子空间 Linear Subspaces 线性无关的相关例题 Span and Linear Independence Example 线性无关的进一步介绍 More on linear independence 关于线性无关 Introduction to Linear Independence 线性组合和向量张成的空间 Linear Combinations and Span 平面之间的距离 The distance between planes 点到平面的距离 Point distance to plane 从平面方程找法线向量 Normal vector from plane equation 向量的三重积展开 Vector Triple Product Expansion 直线的参数表示 Parametric Representations of Lines 求解3×3矩阵的特征向量和特征空间 Eigenvectors and Eigenspaces for a 3×3 matrix 求解3×3矩阵的特征值 Eigenvalues of a 3×3 matrix 求解特征向量和特征空间 Finding Eigenvectors and Eigenspaces example 特征值公式的证明 Proof of formula for determining Eigenvalue 特征向量和特征值的引入 Linear Algebra Introduction to Eigenvalues and Eigenvector 过程的三个基础向量的例子 Gram-Schmidt example with 3 basis vectors 过程的例子 Gram-Schmidt Process Example Gram-Schmidt过程 The Gram-Schmidt Process 正交矩阵的保角性和保长性 Orthogonal matrices preserve angles and lengths 向量范例 Vector Examples 正交基下到子空间的投影 Projections onto subspaces with orthonormal bases 标准正交基下的坐标 Coordinates with respect to orthonormal bases 标准正交基简介 Introduction to Orthonormal Bases 一个替补基底变换矩阵的例子(2) Alternate Basis Transformation Matrix Example Part 2 对应一个基底的变换矩阵 Transformation Matrix with Respect to a Basis 可逆基向量矩阵变换 Invertible Change of Basis Matrix 向量简介 Introduction to Vectors 基变换的矩阵 Change of Basis Matrix 向量在一组基下的坐标 Coordinates with Respect to a Basis 另一个有关最小二乘的例子 Another Least Squares Example 有关最小二乘的例子 Least Squares Examples 最小二乘逼近 Least Squares Approximation 投影是子空间中距离原向量最近的向量 Projection is closest vector in subspace 关于投影的矩阵的另一个例子 Another Example of a Projection Matrix 子空间投影矩阵的例子 Subspace Projection Matrix Example 子空间上的投影是线性变换 A Projection onto a Subspace is a Linear Transform 平面上投影的可视化 Visualizing a projection onto a plane 求解三元方程组 Solving 3 Equations with 3 Unknowns 子空间上的投影 Projections onto Subspaces 证明(A转置)A是可逆的 Showing that A-transpose x A is invertible 方程Ax=b在行空间中的解的例子 Rowspace Solution to Ax=b example 方程Ax=b的行空间中的解 Unique rowspace solution to Ax=b 正交补空间的正交补空间 Orthogonal Complement of the Orthogonal Complement 用子空间中的向量表示Rn中的向量 Representing vectors in Rn using subspace members dim(V) + dim(正交补)=n dim(V) + dim(orthogonal complement of V) 矩阵A的秩等于A转置的秩 Rank(A) = Rank(transpose of A) 三元线性方程 3-variable linear equations 矩阵简介 Introduction to matrices 正交补 Orthogonal Complements 改变坐标系有助于求出变换 Changing coordinate systems to help find a transformation n×n矩阵的行列式 n×n Determinant 外积和角度正弦函数之间关系的证明 Proof- Relationship between cross product and sin of angle 将投影到一条线表达为矩阵向量的乘积 Expressing a Projection on to a line as a Matrix Vector products 可逆性和f(x)=y解唯一性等价的证明 Proof Invertibility implies a unique solution to f(x)=y 计算正交基下到子空间的投影矩阵 Finding projection onto subspace with orthonormal basis example 计算镜像变换矩阵 Example using orthogonal change-of-basis matrix to find transformation matrix 说明特征基有利于构造合适的坐标 Showing that an eigenbasis makes for good coordinate systems 求解一个2×2矩阵的特征值的一个例子 Example solving for the eigenvalues of a 2×2 matrix 映上和一对一和可逆性的联系 Relating invertibility to being onto and one-to-one 线性变换的加法运算和数乘运算 Sums and Scalar Multiples of Linear Transformations 原像和核的相关例子 Preimage and Kernel Example 变换的像空间im(T) im(T)-Image of a Transformation 线性变换的矩阵向量乘积表示 Linear Transformations as Matrix Vector Products 矩阵向量乘法与线性变换 Matrix Vector Products as Linear Transformations 线性变换 Linear Transformations 向量变换 Vector Transformations 函数的深入理解 A more formal understanding of functions 证明候选基底确实张成C(A)空间 Showing that the candidate basis does span C(A) 基底列和主列的关系 Showing relation between basis cols and pivot columns 列空间的维数或秩 Dimension of the Column Space or Rank 零空间的维数或零度 Dimension of the Null Space or Nullity 证明任意子空间基底数目相同 Proof-Any subspace basis has same number of elements 把列空间想象成三维空间上的平面 Visualizing a Column Space as a Plane in R3 零空间与列空间 Null Space and Column Space Basis 矩阵的列空间 Column Space of a Matrix 零空间3-零空间与线性无关的关系 Null Space 3- Relation to Linear Independence 零空间2-矩阵零空间计算 Null Space 2- Calculating the null space of a matrix 零空间的正交补 Orthogonal Complement of the Nullspace 一个替补基底变换矩阵的例子(1) Alternate Basis Transformation Matrix Example Part 1

物理 Physics

向心加速度公式图形理解 Visual Understanding of Centripetal Acceleration Formula 向心力和向心加速度直观解释 Centripetal Force and Acceleration Intuition 抛射运动5 Projectile motion (part 5) 抛射运动4 Projectile motion (part 4) 抛射运动3 Projectile motion (part 3) 抛射运动2 Projectile motion (part 2) 抛射运动1 Projectile motion (part 1) 用有序对符号表示抛射运动 Projectile Motion with Ordered Set Notation 用单位向量表示抛射运动2 Projectile Motion with Unit Vectors (part 2) 用单位向量表示抛射运动 Projectile Motion with Unit Vectors 单位向量表示第2部分 Unit Vector Notation (part 2) 扭矩介绍 Introduction to Torque g的重力场解释 Viewing g as the value of Earth's Gravitational Field Near the Surface 物体图像高度和距离的关系式 Object Image and Focal Distance Relationship 凸透镜练习 Convex Lens Examples 凸透镜 Convex Lenses 凸抛物面镜 Convex Parabolic Mirrors 抛物面镜2 Parabolic Mirrors 2 抛物面镜和实像 Parabolic Mirrors and Real Images 虚像 Virtual Image 全反射 Total Internal Reflection 斯涅尔定律例题2 Snell's Law Examples 2 斯涅尔定律例题1 Snell's Law Examples 1 折射和斯涅耳定律 Refraction and Snell's Law 镜面反射和漫反射 Specular and Diffuse Reflection 2 镜面反射和漫反射 Specular and Diffuse Reflection 马赫数 Mach Numbers 当波源和波速相同时的情况 When the source and the wave move at the same velocity 当波源移动时的多普勒效应公式 Doppler effect formula when source is moving away 观察到的频率的多普勒效应公式 Doppler effect formula for observed frequency 多普勒效应介绍 Introduction to the Doppler Effect 波介绍 Introduction to Waves 点乘和叉乘 Dot vs. Cross Product 点乘 The dot product 磁学12 Magnetism 12 磁学11 Magnetism 11 磁学10 Magnetism 10 磁学9 Magnetism 9 磁学8 Magnetism 8 磁学7 Magnetism 7 磁学6 Magnetism 6 磁学5 Magnetism 5 磁学4 Magnetism 4 磁学3 Magnetism 3 磁学2 Magnetism 2 磁学介绍 Introduction to Magnetism 叉乘与力矩 Cross Product and Torque 叉乘2 Cross product 2- 叉乘1 Cross product 1- 电路4 Circuits (part 4) 电路3 Circuits (part 3) 电路2 Circuits (part 2) 电路1 Circuits (part 1) 电容 Capacitance 电压 Voltage 电势能2 Electric Potential Energy (part 2) 电势能 Electric Potential Energy- 无限大平板的电场的证明2 Proof (Advanced)_ Field from infinite plate (part 2) 无限大平板的电场的证明1 Proof (Advanced)_ Field from infinite plate (part 1) 静电学2 Electrostatics (part 2) 静电学1 Electrostatics (part 1) 热力学5 Thermodynamics (part 5) 热力学4 Thermodynamics (part 4) 热力学3 Thermodynamics (part 3) 热力学2 Thermodynamics (part 2) 物理 Thermodynamics (part 1) 液体12 Fluids (part 12) 液体11 Fluids (part 11) 液体10 Fluids (part 10) 液体9 Fluids (part 9) 液体8 Fluids (part 8) 液体7 Fluids (part 7) 液体6 Fluids (part 6) 液体5 Fluids (part 5) 液体4 Fluids (part 4) 液体3 Fluids (part 3) 液体2 Fluids (part 2) 流体1 Fluids (part 1) 简谐运动第3部分 Harmonic Motion Part 3 (no calculus) 简谐运动第2部分 Harmonic Motion Part 2 (calculus) 简谐运动介绍 Introduction to Harmonic Motion 弹簧势能举例 Spring potential energy example (mistake in math) 弹簧势能 Potential energy stored in a spring 弹簧和胡克定律介绍 Intro to springs and Hooke's Law 重力第2部分 Gravitation (part 2) 牛顿重力法则介绍 Introduction to Newton's Law of Gravitation 角动量守恒定律 Conservation of angular momentum 空间站轨道速率 Space Station Speed in Orbit 空间站处由于重力导致的加速度 Acceleration Due to Gravity at the Space Station 过山车答案2 Loop De Loop Answer part 2 过山车答案1 Loop De Loop Answer part 1 单位向量表示的点乘和叉乘运算 Calculating dot and cross products with unit vector notation 物体图像和焦距之间的关系式 Object Image and Focal Distance Relationship (Proof of Formula) 周期波的幅度,周期,频率,波长 Amplitude, Period, Frequency and Wavelength of Periodic Waves 绕圈问题 Loop De Loop Question 用微积分证明向心加速度公式 Calculus proof of centripetal acceleration formula 角速度和速率的关系 Relationship between angular velocity and speed

生物 Biology

扩散与渗透 Diffusion and Osmosis 细胞结构 Parts of a cell CAM植物 CAM Plants C-4光合作用 C-4 Photosynthesis 光呼吸 Photorespiration 光合作用-卡尔文循环 Photosynthesis, Calvin Cycle 光合作用-光反应与光合磷酸化 Photosynthesis Light Reactions and Photophosphorylation 光合作用-光反应1 Photosynthesis Light Reactions 1 光合作用概述 Photosynthesis 氧化磷酸化与化学渗透 Oxidative Phosphorylation and Chemiosmosis 电子传递链 Electron Transport Chain 克雷布斯循环 Krebs Circle 从生物学角度复习氧化还原反应 Oxidation and Reduction Review From Biological 细胞呼吸概述 Introduction to Cellular Respiration Weinberg原理 Hardy-Weinberg Principle-Hardy-Weinberg 庞尼特方格 Punnett Square Fun 遗传概述 Introduction to Heredity 减数分裂 Phases of Meiosis ATP,三磷酸腺苷 ATP,Adenosine Triphosphate-ATP 染色体,染色单体,染色质等 Chromosomes, Chromatids, Chromatin, etc- 物种变异 Variation in a Species 分类学与生命树 Taxonomy and the Tree of Life 物种 Species 肾元中的次级主动运输 Secondary Active Transport in the Nephron DNA DNA 肾与肾元 The Kidney and Nephron 炎性反应 Inflammatory Response 复习B细胞与T细胞 Review of B cells, CD4+ T cells and CD8+ T cells 细胞毒性T细胞 Cytotoxic T Cells 辅助T细胞 Helper T Cells APC与MHC II复合体 Professional Antigen Presenting Cells (APC) and MHC II B细胞 B Lymphocytes (B cells) 免疫反应的种类 Types of immune responses Innate and Adaptive.Humoral vs Cell-Mediated 吞噬细胞在先天性免疫中的作用 Role of Phagocytes in Innate or Nonspecific Immunity 肌细胞的构造 Anatomy of a muscle cell 肌浆网在肌细胞内的作用 Role of the Sarcoplasmic Reticulum in Muscle Cells 肌凝蛋白与肌动蛋白 Myosin and Actin 神经元突触 Neuronal Synapses 神经元内的跳跃传导 Saltatory Conduction in Neurons 电紧张电位与动作电位 Electrotonic and Action Potentials 关于钠钾泵的更正 Correction to Sodium and Potassium Pump Video 钠钾泵 Sodium Potassium Pump 神经元构造 Anatomy of a Neuron 血红蛋白 Hemoglobin 循环系统与心脏 Circulatory System and the Heart 红细胞 Red blood cells 肺与肺系统 The Lungs and Pulmonary System 原肌凝蛋白和肌钙蛋白及它们在肌肉收缩时扮演的角色 Tropomyosin and troponin and their role in regulating muscle contraction

统计学 Statistics

基础化学 Chemistry

三角形 1 Triangle I

多边形、四边形和平行四边形 Polygon,Quadrilateral,Parallelogram