Thank you very much it suddenly clicked for me after I factored out the (k+1)Please read and follow the forum guidelines, F.AAAA.
Start by factoring out the common factor: (k+1)^2.
If it helps you to see how, you can always make a temporary substitution first.
Let z = k+1
Then you have:
1/4 * k^2 * z^2 + z^3
After you factor out the common factor z^2, back-substitute k+1 for z in your result. Then show us what you got.
The next step will involve a factorization like these examples:
1/2*t + t + 1 = 1/2(t + 2t + 2)
1/3*t + t + 1 = 1/3(t + 3t + 3)
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