Question

Use mathematical induction to prove the formula for every positive interger, n.
3+7+11+15+...+(4n-1)=n(2n+1)

Answer 1

@bahrom7893

Answer 2

hmm do we prove that it's true for n-1 and n, or n and n+1?

Answer 3

btw i have no clue ow to do this at the moment..

Answer 4

@imranmeah91 take a look

Answer 5

@myininaya

Answer 6

lol myininaya will show up and say @amistre64 and then amistre will call for satellite.. lol just kiddin

Answer 7

step 1 basecase

3 = 1(2 +1) yes

assume true for some n prove true for n+1

3+7+11+15+...+(4n-1)=n(2n+1)

consider the n+1 case

add (4(n+1) -1) to each side
= 4n +3

f(n+1) = n(2n+1) + 4n+3
= 2n^2 +n + 4n +3 =? (n+1)(2n +2 +1)
=? (n+1) (2n+3)
=? 2n^2 +5n +3
Yes

Answer 8

I got it :P

Answer 9

Kumar got it too!

Answer 10

I was late :(