Uh oh! Wolfram|Alpha doesn't run without JavaScript.
Please enable JavaScript. If you don't know how, you can find instructions
here
.
Once you've done that, refresh this page to start using Wolfram|Alpha.
Plot[{-Cos[2θ],Cos[θ],Abs[-Cos[2θ]]},{θ,0,Pi/3}]
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random