1. ## Calculator help

We are doing integrals and I have the problem that is the integral from 0 to pi/2 2cos^5x(dx) n=4 therefore, dX=pi/8

We are asked for the midpoint values and I got

(pi/8) (2 cos^5(pi/16) + 2 cos^5(3 pi/16) +2 cos^5(5pi/6)+2 cos^5(7pi/16))

I tried putting this into the google calculator and it didn't give me an answer. I assume that the " ^5 " is giving it a problem but I'm not sure. Any tips?

2. ## Re: Calculator help

To use a calculator, you will need to enter things like \displaystyle \begin{align*} \cos^n{(bx)} \end{align*} as ( cos(b*x) )^n .

3. ## Re: Calculator help

Another tip: make sure the calculator is in "radians" mode. When you have $\cos\frac{5\pi}{16}$, the $\frac{5\pi}{16}$ is $\frac{5\pi}{16}$ radians, not $\frac{5\pi}{16}$ degrees. You undoubtedly know that, but it's easy to forget to make sure the calculator is in the right mode.

- Hollywood

4. ## Re: Calculator help

thank you! it works!