Show, with induction that
$1^2 + 2^2 + .... + n^2 = \frac{n(n+1)(2n+1)}{6}$
My attempt
Case 1: n = 1
$LHS = 1^2$
$RHS = \frac{(1+1)(2+1)}{6} = \frac{2*3}{6} = 1$
Case 2: n = p
$LHS_{p} = 1^2 + 2^2 + ... + p^2$
$RHS_{p} = \frac{p(p+1)(2p+1)}{6}$
Case 3: n = p + 1
$LHS_{p+1} = 1^2+2^2+....+p^2+(p+1)^2$
$RHS_{p+1} = \frac{(p+1)((p+1)+1)(2(p+1)+1)}{6}$
Now to show this with induction I think i need to show that
$RHS_{p+1} = RHS_{p} + (p+1)^2$
$RHS_{p+1} = \frac{p(p+1)(2p+1)}{6} + (p+1)^2$
So I need to rewrite
$RHS_{p+1} = \frac{(p+1)((p+1)+1)(2(p+1)+1)}{6} $to be equal to $\frac{p(p+1)(2p+1)}{6} + (p+1)^2$
Anyone see how I can do that? Or got any other solution?
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