Calculus

                                                         Integrals 

Table of Integrals 
Power of x.
(integral)xn dx = x(n+1) / (n+1) + C 
(n  -1)  Proof
(integral)1/x dx = ln|x| + C
Exponential / Logarithmic
(integral)ex dx = ex + C  
Proof 
(integral)bx dx = bx / ln(b) + C  
ProofTip!
(integral)ln(x) dx = x ln(x) - x + C  
Proof
Trigonometric
(integral)sin x dx = -cos x + C  
Proof
(integral)csc x dx = - ln|CSC x + cot x| + C  
Proof
(integral)COs x dx = sin x + C  
Proof
(integral)sec x dx = ln|sec x + tan x| + C  
Proof
(integral)tan x dx = -ln|COs x| + C  
Proof
(integral)cot x dx = ln|sin x| + C  
Proof
Trigonometric Result
(integral)COs x dx = sin x + C   
Proof
(integral)CSC x cot x dx = - CSC x + C   
Proof
(integral)sin x dx = COs x + C   
Proof
(integral)sec x tan x dx = sec x + C   
Proof
(integral)secdx = tan x + C   
Proof
(integral)cscdx = - cot x + C   
Proof
Inverse Trigonometric
(integral)arcsin x dx = x arcsin x + sqrt(1-x2) + C
(integral)arccsc x dx = x arccos x - sqrt(1-x2) + C
(integral)arctan x dx = x arctan x - (1/2) ln(1+x2) + C
Inverse Trigonometric Result
 
(integral) dx 
sqrt(1 - x2)
 = arcsin x + C
 
(integral) dx 
sqrt(x2 - 1)
 = arcsec|x| + C
 
(integral) dx 
1 + x2
 = arctan x + C
 
 
Useful Identitiesarccos x = pi/2 - arcsin x 
(-1 <= x <= 1) 
arccsc x = pi/2 - arcsec x 
(|x| >= 1) 
arccot x = pi/2 - arctan x 
(for all x)
 
Hyperbolic
(integral)sinh x dx = cosh x + C   
Proof
(integral)csch x dx = ln |tanh(x/2)| + C   
Proof
(integral)cosh x dx = sinh x + C   
Proof
(integral)sech x dx = arctan (sinh x) + C
(integral)tanh x dx = ln (cosh x) + C   
Proof
(integral)coth x dx = ln |sinh x| + C  
Proof

Integral Identities
Formal Integral Definition:
(integral)(a to b) f(x) dx = lim (d -> 0) (sum) (k=1..n) f(X(k)) (x(k) - x(k-1)when...
a = x0 < x1 < x2 < ... < xn = b
d = max (x1-x0, x2-x1, ... , xn - x(n-1))
x(k-1) <= X(k) <= x(k)     k = 1, 2, ... , n
(integral)(a to b) F '(x) dx = F(b) - F(a) (Fundamental Theorem for integrals of derivatives)
(integral)a f(x) dx = a(integral) f(x) dx (if a is constant)
(integral)f(x) + g(x) dx = (integral)f(x) dx + (integral)g(x) dx
(integral)(a to b) f(x) dx = (integral)f(x) dx | (a b)
(integral)(a to b) f(x) dx + (integral)(b to c) f(x) dx = (integral)(a to c) f(x) dx
(integral)f(u) du/dx dx = (integral)f(u) du (integration by substitution)

Special Functions
Some of these functions I have seen defined under both intervals (0 to x) and (x to inf). In that case, both variant definitions are listed.
gamma = Euler's  constant = 0.5772156649...
(x) = Gamma(x) = (integral)(0 to inf)t^(x-1) e^(-t)dt (Gamma function)
B(x,y) = (integral)(0 to 1)t^(x-1) (1-t)^(y-1)DT 
(Beta function) 
Ei(x) = (integral)(x to inf)e^(-t)/t DT (exponential integral) or it's variant,NONEQUIVALENT form:
Ei(x) =  + ln(x) + (integral)(0 to x)(e^t - 1)/t DT = gamma + ln(x) + (sum)(n=1..inf)x^n/(n*n!)
li(x) = (integral)(2 to x)1/ln(t) DT (logarithmic integral)
Si(x) = (integral)(x to inf)sin(t)/t DT (sine integral) or it's variant,NONEQUIVALENT form:
Si(x) = (integral)(0 to x)sin(t)/t DT = PI/2 - (integral)(x to inf)sin(t)/t DT

Ci(x) = (integral)(x to inf)cos(t)/t DT (cosine integral) or it's variant,NONEQUIVALENT form:
CI(x) = - (integral)(x to inf)COs(t)/t DT = gamma + ln(x) + (integral)(0 to x) (COs(t) - 1) / t DT (cosine integral)

Chi(x) = gamma + ln(x) + (integral)(0 to x)(cosh(t)-1)/t DT (hyperbolic cosine integral)
Shi(x) = (integral)(0 to x)sinh(t)/t DT (hyperbolic sine integral)
Erf(x) = 2/PI^(1/2)(integral)(0 to x)e^(-t^2) DT = 2/sqrtPI (sum)(n=0..inf) (-1)^nx^(2n+1) / ( n! (2n+1) ) (error function)
FresnelC(x) = (integral)(0 to x)COs(PI/2 t^2) DT
FresnelS(x) = (integral)(0 to x)sin(PI/2 t^2) DT
dilog(x) = (integral)(1 to x)ln(t)/(1-t) DT
Psi(x) = (d/dx)ln(Gamma(x))
Psi(n,x) = nth derivative of Psi(x)
W(x) = inverse of x*e^x
sub n (x) = (e^x/n!)( x^n e^(-x) ) (n) (laguerre polynomial degree n. (n) meaning nth derivative)
Zeta(s) = (sum)(n=1..inf) 1/n^s
Dirichlet's beta function B(x) = (sum)(n=0..inf) (-1)^n / (2n+1)^x

                           Derivatives

Table of Derivatives
Power of x.
 c = 0 x = 1 xn = n x(n-1) 
Proof
Exponential / Logarithmic
 ex = ex 
Proof
 bx = bx ln(b) 
Proof
 ln(x) = 1/x 
Proof
Trigonometric
 sin x = cos x 
Proof
 csc x = -csc x cot x 
Proof
 cos x = - sin x 
Proof
 sec x = sec x tan x 
Proof
 tan x = sec2 x 
Proof
 cot x = - csc2 x 
Proof
Inverse Trigonometric
 arcsin x  = 
sqrt(1 - x2)
 
 arccsc x = -1 
|x| sqrt(x2 - 1)
 
 arccos x =  -1 
sqrt(1 - x2)
 
 arcsec x = 
|x| sqrt(x2 - 1)
 
 arctan x = 
1 + x2
 
 arccot x = -1 
1 + x2
 
Hyperbolic
 sinh x = cosh x 
Proof
 csch x = - coth x csch x 
Proof
 cosh x = sinh x 
Proof
 sech x = - tanh x sech x 
Proof
 tanh x = 1 - tanh2 x 
Proof
 coth  x = 1 - coth2 x 
Proof
  
Differentiation Identities

Definitions of the Derivative:
df / dx = lim (dx -> 0) (f(x+dx) - f(x)) / dx (right sided)
df / dx = lim (dx -> 0) (f(x) - f(x-dx)) / dx (left sided)
df / dx = lim (dx -> 0) (f(x+dx) - f(x-dx)) / (2dx) (both sided)
(d/dx)(integral)(a to x) f(t) dt = f(x) (Fundamental Theorem for Derivatives)

(d/dx)c f(x) = c proof
(d/dx)f(x) (c is a constant)
(d/dx) (f(x) + g(x)) = (d/dx) f(x) + (d/dx) g(x) proof
(d/dx) f(g(x)) = (d/dg) f(g) * (d/dx) g(x) (chain rule) proof
(d/dx) f(x)g(x) = f'(x)g(x) + f(x)g '(x) (product rule)
(d/dx) f(x)/g(x) = ( f '(x)g(x) - f(x)g '(x) ) / g^2(x) (quotient rule)

Partial Differentiation Identities

if f( x(r,s), y(r,s) )
df / dr = df / dx * dx / DR + df / dy * dy / DR
df / ds = df / dx * dx / Ds + df / dy * dy / Ds
if f( x(r,s) )
df / DR = df / dx * dx / DR
df / Ds = df / dx * dx / Ds
directional derivative
df(x,y) / d(Xi sub a) = f1(x,y) cos(a) + f2(x,y) sin(a)
(Xi sub a) = angle counterclockwise from pos. x axis.
 Derivatives: Min, Max, Critical Points...
Asymptotes
Definition of a horizontal asymptote: The line y = y0 is a "horizontal asymptote" of f(x) if and only if f(x) approaches y0 as x approaches + or - inf.Definition of a vertical asymptote: The line x = x0 is a "vertical asymptote" of f(x) if and only if f(x) approaches + or - inf as x approaches x0from the left or from the right.
Definition of a slant asymptote: the line y = ax + b is a "slant asymptote" of f(x) if and only if lim (x-->+/-inf) f(x) = ax + b.
Concavity
Definition of a concave up curve: f(x) is "concave up" at x0 if and only iff '(x) is increasing at x0Definition of a concave down curve: f(x) is "concave down" at x0 if and only if f '(x) is decreasing at x0
The second derivative test: If f ''(x) exists at x0 and is positive, then f ''(x)is concave up at x0. If f ''(x0) exists and is negative, then f(x) is concave down at x0. If f ''(x) does not exist or is zero, then the test fails.
Critical Points
Definition of a critical point: a critical point on f(x) occurs at x0 if and only if either f '(x0) is zero or the derivative doesn't exist.
Extrema (Maxima and Minima)
Local (Relative) ExtremaDefinition of a local maxima: A function f(x) has a local maximum at x0 if and only if there exists some interval I containing x0 such that f(x0) >= f(x) for all x in I.
Definition of a local minima: A function f(x) has a local minimum at x0 if and only if there exists some interval I containing x0 such that f(x0) <= f(x) for all x in I.
Occurrence of local extrema: All local extrema occur at critical points, but not all critical points occur at local extrema.
The first derivative test for local extrema: If f(x) is increasing (f '(x) > 0) for all x in some interval (a, x0] and f(x) is decreasing (f '(x) < 0) for all x in some interval [x0, b), then f(x) has a local maximum at x0. If f(x) is decreasing (f '(x) < 0) for all x in some interval (a, x0] and f(x) is increasing (f '(x) > 0) for all x in some interval [x0, b), then f(x) has a local minimum at x0.
The second derivative test for local extrema: If f '(x0) = 0 and f ''(x0) > 0, then f(x) has a local minimum at x0. If f '(x0) = 0 and f ''(x0) < 0, then f(x) has a local maximum at x0.
Absolute Extrema
Definition of absolute maxima: y0 is the "absolute maximum" of f(x) on I if and only if y0 >= f(x) for all x on I.
Definition of absolute minima: y0 is the "absolute minimum" of f(x) on I if and only if y0 <= f(x) for all x on I.
The extreme value theorem: If f(x) is continuous in a closed interval I, then f(x) has at least one absolute maximum and one absolute minimum in I.
Occurrence of absolute maxima: If f(x) is continuous in a closed interval I, then the absolute maximum of f(x) in I is the maximum value of f(x) on all local maxima and endpoints on I.
Occurrence of absolute minima: If f(x) is continuous in a closed interval I, then the absolute minimum of f(x) in I is the minimum value of f(x) on all local minima and endpoints on I.
Alternate method of finding extrema: If f(x) is continuous in a closed interval I, then the absolute extrema of f(x) in I occur at the critical points and/or at the endpoints of I.
(This is a less specific form of the above.)
Increasing/Decreasing Functions
Definition of an increasing function: A function f(x) is "increasing" at a point x0 if and only if there exists some interval I containing x0 such that f(x0) > f(x) for all x in I to the left of x0 and f(x0) < f(x) for all x in I to the right of x0.Definition of a decreasing function: A function f(x) is "decreasing" at a point x0 if and only if there exists some interval I containing x0 such that f(x0) < f(x) for all x in I to the left of x0 and f(x0) > f(x) for all x in I to the right of x0.
The first derivative test: If f '(x0) exists and is positive, then f '(x) is increasing at x0. If f '(x) exists and is negative, then f(x) is decreasing at x0. If f '(x0) does not exist or is zero, then the test tells fails.
Inflection Points
Definition of an inflection point: An inflection point occurs on f(x) at x0 if and only if f(x) has a tangent line at x0 and there exists and interval I containing x0 such that f(x) is concave up on one side of x0 and concave down on the other side.
Series (Summation) Expansions
Basic Properties
Convergence Tests
Function-->Summation and Summation-->Function Conversions
Select function f(x) to expand into a summation 
f(x) = sum ?
Select term an in summation to simplify:
sum an = ?
Exponential / Logarithm Functions 
  f(x) = e; e-1; e x 
  f(x) = ln(x) Root Functions 
  f(x) = sqrt(x); 1/sqrt(x)
Geometric Series 
  an = r n Power Series 
  an = n; n 2; n 3; ...
  an = 1/n; 1/n 2; 1/n 3; 1/n 4;
1/n 5; 1/n 6; 1/n 7; 1/n 8;
1/n 9; 1/n 10; 1/n p

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