What is the integral of 4cos(2θ) ?

The integral of 4cos(2θ) is 2sin(2θ)+C

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

integral of 4cos(2θ)

\int 4 cos (2 θ) d θ

2 sin (2 θ) + C

Solution steps

\int 4 cos (2 θ) d θ

Take the constant out:

\int a \cdot f (x) d x = a \cdot \int f (x) d x

= 4 \cdot \int cos (2 θ) d θ

Apply u-substitution

= 4 \cdot \int cos (u) \frac{1}{2} d u

Take the constant out:

\int a \cdot f (x) d x = a \cdot \int f (x) d x

= 4 \cdot \frac{1}{2} \cdot \int cos (u) d u

Use the common integral:

\int cos (u) d u = sin (u)

= 4 \cdot \frac{1}{2} sin (u)

Substitute back

u = 2 θ

= 4 \cdot \frac{1}{2} sin (2 θ)

Simplify

4 \cdot \frac{1}{2} sin (2 θ) : 2 sin (2 θ)

= 2 sin (2 θ)

Add a constant to the solution

= 2 sin (2 θ) + C