Q: If f(r)=3 [r/(31/2)]2 (3r -1)-1
simplify this expression and find df/dr.
A: 3 [r/(31/2)]2 (3r -1)-1
= 3 [r2/3] r/3 = r3/3. Thus df/dr = 3r2/3
Answer to 2 point bonus question about the Simpsons:
After Bart switches IQ tests with the smart kid, his new teacher at the school for talented and gifted kids gives this a problem and all of the other kids get the joke. Notice that df = r2 dr or r dr r (har de har har).