1
$\begingroup$

I've been struggling with learning mathematical induction in the past couple of days and I think I may have found out why but I still can't solve the problem due to a possible deficiency in foundational algebraic skills.

I'm not able to post an image as my account is too new but my textbook solution labels,

"replace 5+9+13+...+(4k+1) with k(2k+3).

It is this step that I always get stuck and I can't seem to see how I can replace the value with what they state in the example.

An explanation or some insight would be extremely helpful, thanks.

$\endgroup$
2
$\begingroup$

Its just sum if AP which is $$\frac{k}{2}(10+(4k-1)4)=2k^2+3k=k(2k+3)$$

$\endgroup$
  • 1
    $\begingroup$ Aha! Thank you, this really helps. $\endgroup$ – user318228 Feb 27 '16 at 12:58
  • $\begingroup$ Welcome :).... ... $\endgroup$ – Archis Welankar Feb 27 '16 at 13:20

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.