12.3#10

I've tried almost two times to figure out what exactly this problem is
asking for in the incorrect box. I've tried a ton of different expressions,
and the generic f(r,theta), f(r,t), etc. I am just very confused as to what
exactly it wants as an answer.

I can handle picky problems, but this is
one silly demand here.

Any idea what is wrong with it?


Thanks!

******
Sometimes webwork does picky, silly things, but this isn't one of those times. You  are given a function of x&y, f(x,y) You just decide to replace x by r and y by t, but that's not the way it works. Remember : x=r cos(t) and y = r sin(t), and you need to substitue these in for x&y.