参考资料
Step-by-step references across 13 categories.
代数:方程
代数:对数
代数:指数
代数:虚数
代数:多项式
代数:三角
微积分
线性代数:矩阵与方程组
Matrix Determinant
Compute 2x2 and 3x3 determinants via the ad - bc rule or cofactor expansion.
det([[1,2],[3,4]])det([[2,0],[1,3]])
Matrix Inverse
Invert a square matrix with the adjugate formula, or detect that it is singular.
inv([[1,2],[3,4]])inv([[4,7],[2,6]])
Matrix Transpose
Swap rows and columns of a matrix.
transpose([[1,2],[3,4]])transpose([[1,2,3],[4,5,6]])
Matrix Multiplication
Multiply two matrices row by column, entry by entry.
[[1,2],[3,4]] * [[5,6],[7,8]][[1,0],[0,1]] * [[2,3],[4,5]]
Systems of Linear Equations
Solve systems of 2 or 3 linear equations by Gaussian elimination. Separate equations with a semicolon.
x + y = 3; x - y = 12x + y = 1; x - y = 1
Eigenvalues & Eigenvectors
Characteristic polynomial, eigenvalues and eigenvectors of 2x2 and 3x3 matrices.
eigenvalues([[2,1],[1,2]])eigenvectors([[2,1],[1,2]])
微积分:微分方程
Separable Differential Equations
Solve first-order separable ODEs by separating variables and integrating. Use y' for the derivative.
y' = x*yy' = 2*y
First-Order Linear Differential Equations
Solve y' + P(x)y = Q(x) with an integrating factor.
y' + 2*y = xy' + y = x
Second-Order Linear ODEs
Constant-coefficient homogeneous equations via the characteristic equation.
y'' + 3*y' + 2*y = 0y'' + 2*y' + y = 0
概率与统计
Descriptive Statistics
Mean, median, mode, variance and standard deviation of a data set.
stats(2, 4, 4, 5, 7)mean(1, 2, 3, 4)
Combinations & Permutations
Factorials, combinations nCr and permutations nPr with expanded factorial steps.
nCr(5, 2)nPr(5, 2)
Binomial Probability
P(X = k) for n independent trials with success probability p.
binomial_p(10, 3, 1/2)binomial_p(6, 2, 1/3)
几何
Right Triangles
Find the hypotenuse or a leg with the Pythagorean theorem.
hypotenuse(3, 4)leg(5, 3)
Triangle Area (Heron)
Area of a triangle from its three sides using Heron's formula.
triangle_area(3, 4, 5)triangle_area(7, 8, 9)
Circles
Area and circumference of a circle, exact (in terms of pi) and approximate.
circle_area(3)circle_circumference(3)
Coordinate Geometry
Distance, midpoint and slope between two points.
distance(1, 2, 4, 6)midpoint(1, 2, 3, 4)