1. ## Inductive Proof

how do you get this problem $[k(k+1)/2]^2 + (k+1)^3$ down to $[(k+1)(k+2)/2]^2$

I'm having troubles with the arithmetic...

2. Wait, is this true?

Factor $(k+2)^2$ out to get $(k+1)^2\left(\frac{k}{2}+(k+1)\right)$. Then combine the terms by getting a common denominator. But, it doesn't seem to give you what claim it does.

3. Yeah I don't get this one either =/

4. so i factored out (k+1)^2 and i got this....1/4(k+1)^2 + (K^2+(k+1))

5. Ah, oops. I factored it incorrectly, myself.

You should have $
(k+1)^2\left(\frac{k^2}{4}+(k+1)\right)=(k+1)^2\le ft(\frac{k^2+4k+4}{4}\right)=(k+1)^2\frac{(k+2)^2} {4}
$

This gives it to you.

6. thanks man!