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Feb
16
awarded  Supporter
Oct
10
comment Prove by induction $\sum_{i=1}^ni^3=\frac{n^2(n+1)^2}{4}$ for $n\ge1$
My algebra is rusty and the intellectual leap to $\frac{(n+1)^2}{4}[n^2+4(n+1)]$ in the first equality escapes me. Can you explain further?
Oct
10
revised Prove by induction $\sum_{i=1}^ni^3=\frac{n^2(n+1)^2}{4}$ for $n\ge1$
deleted 3 characters in body
Oct
10
awarded  Editor
Oct
10
revised Prove by induction $\sum_{i=1}^ni^3=\frac{n^2(n+1)^2}{4}$ for $n\ge1$
Fixed formatting of equalities in second equation
Oct
10
comment Prove by induction $\sum_{i=1}^ni^3=\frac{n^2(n+1)^2}{4}$ for $n\ge1$
@MichaelHardy Thanks for pointing out my misused arrow. The post has been edited to fix this.
Oct
10
awarded  Student
Oct
10
asked Prove by induction $\sum_{i=1}^ni^3=\frac{n^2(n+1)^2}{4}$ for $n\ge1$