Integrating Sin

[duki]

Homework Statement

$$\int\sin(6\theta) d\theta$$

Homework Equations

The Attempt at a Solution

$$\int6\cos6\theta$$

Am I close?

 

[Feldoh]

If it helps do a u-sub where u=6theta

Or you could think of it like this:

If we take the derivative of $$\frac{d}{d \theta}(-cos(\theta)) = sin(\theta)$$. That's sort of like the anti-derivative which you seek.

If we take the derivative of $$\frac{d}{d \theta}(-cos(6 \theta)) = 6sin(6 \theta)$$.

So from there it's easy to see that$$\int\sin(6\theta) d\theta = \frac{-cos(6\theta)}{6}$$

 

[duki]

errr...

$$\frac{-\cos6\theta}{6}$$

 

[duki]

thanks :)

 

[Feldoh]

Yeah looks right^^