4
$\begingroup$

I am wondering if the third to last equation is correct, where I factored out the $(-1)^k$. The first term is inside the parenthesis is $(-1)^{-1}$. Is this correct? If I multiply it out again, wont the $(-1)$'s cancel? I'm not 100% sure even though i proved it. I am assuming $(-1)^k$ multiplied by $(-1)^{-1}$ is $(-1)^{k-1}$ Proof

$\endgroup$
2
  • 2
    $\begingroup$ Correct${}{}{}$ $\endgroup$
    – peterwhy
    Commented Sep 19, 2013 at 4:13
  • 2
    $\begingroup$ Agreed. Well done. $\endgroup$ Commented Sep 19, 2013 at 4:44

1 Answer 1

1
$\begingroup$

Your proof is completely correct.

$\endgroup$
1
  • $\begingroup$ where did the $(-1)^k$ go between lines 1 and 2 $\endgroup$
    – Benny
    Commented Sep 15, 2022 at 11:33

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .