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.
y''+9y = 2cos(3x), y(0)=0, y'(0)=1
y''+9y = 2cos(3x), y(0)=0, y'(0)=1
Natural Language
Math Input
Extended Keyboard
