Calculus 2 Cheatsheet

Definitions, Symbols, Formulas, and Notes — All in One Place.

Show Shortcuts

Evaluating Integrals

Term

Definition

Formula

Example

Integration by PartsA technique used to integrate the product of two functions by transforming it into a simpler form. udv=uvvdu where u and v are differentiable functions of x.

1. Consider the integral xsin(x)dx 
 u=x,dv=sin(x)dx
du=dx,v=cos(x)
  
2. Applying the integration by parts formula:
   xsin(x)dx=xcos(x)cos(x)dx
   =xcos(x)+sin(x)+C

Trigonometric SubstitutionA technique used to simplify integrals involving square roots of quadratic expressions using trigonometric identities.

 Consider the integral 4x2dx
We can use trigonometric substitution with x=2sin(θ):
  dx=2cos(θ)dθ
   4x2=4(2sin(θ))2=2cos(θ)
   The integral becomes:  2cos2(θ)dθ

Partial Fraction DecompositionA method used to decompose a rational function into the sum of simpler fractions, making it easier to integrate.

  1. Consider the rational function 2x+3x2+3x+2:
       
     The denominator factors as (x+1)(x+2), so we write:
       
       2x+3x2+3x+2=Ax+1+Bx+2
      
  2. Multiplying both sides by x2+3x+2 and simplifying, we find the values of A and B.
    2x+3x2+3x+2=Ax+1+Bx+2
  3. Multiplying both sides by (x+1)(x+2) to clear the denominators, we get:

    2x+3=A(x+2)+B(x+1)

  4. Expanding and collecting like terms:

    2x+3=Ax+2A+Bx+B

  5. For x terms: A+B=2

    For constant terms: 2A+B=3

    Solving these equations, we find A=1 and B=1.

  6. Therefore, the decomposition is 2x+3x2+3x+2=1x+1+1x+2
     

Applications of Integration

Improper Integrals

Sequences

Series

Parametric Equations and Polar Coordinates

Common Integrals