This problem is for a discrete math class, but requires factoring/simplifying. I haven't attempted anything like this in about 10 years.

I need $\displaystyle (\frac{(k(k+1))}{2})^2 + (k+1)^3$

to look like this: $\displaystyle (\frac{(k+1)(k+2)}{2})^2$

If that's possible. This may be asking alot, but a brief explanation of the simplification would be fantastic.

Thank you.