Trigonometric Integrals

I.  Homework

II.  Six Basic Trig Integrals

Since the integral of a function is the antiderivative, we arrive at the following identities immediately:

Example

Find

int sin (2x) dx

Solution

We use u substitution:

u = 2x, du = 2dx, du/2 = dx gives

1/2 int sin(u) du = -1/2cos u + C = -1/2 cos(2x) + C

We will work out many other exercises in class.