# Calculator help

• Feb 15th 2013, 11:33 AM
Steelers72
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?
• Feb 15th 2013, 02:31 PM
Prove It
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 .
• Feb 15th 2013, 06:40 PM
hollywood
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
• Feb 15th 2013, 07:42 PM
Steelers72
Re: Calculator help
thank you! it works!