Math Induction MiniLesson

[MrGameOwnage]

That was good, thank you :)

[cqlatuu]

that mouse clicking is so annoying.

[starrgazer07]

This was unbelievably helpful! Thank you so much for explaining this!

[einTyp25]

How can I solve exercises like

1+2+3+...+n= Σ {above stands n; on the right i; at the bottom i=1}  = [n(n+1)]/2

[davidtamuna1]

yo helped me so much :) thank you man yua are genius :)

[msupokergod]

(5^n - 1) is divisible by four by assumption. We just need to know that 5^(n+1) -1 is divisible by 4 **IF we already know** that (5^n - 1) is divisible by four. So we assume the former, derive the latter, prove it for n=1, thus it is true for n=2, so since its true for n=2 its true for n=3 and so on

[exchangeisno]

Where was the proof that (5^n - 1) was divisible by four? You only proved that it's true for 1 by substitutng 1 in the expression. You didn't prove it is true for any other 'n'.

You broke the expression down nicely to a term containing two expressions ie (4x5^n) + (5^n - 1) the first term is clearly a multiple of four therefore poved...where is the ''proof'' for

(5^n -1)? . It is true, of course but you haven't proved it. This sort of half proof is really sloppy.

[falsafi92]

thanks alottt :) :D :)

[oopziesx3]

thank you!!

[TheWakeUpCall]

Very helpful.

[lef67]

Yeah great! Thanks, this was so hard to understand from the book. But now I got it :)

[wynjones1]

Thanks for this, I've been struggling with this for an entire week, now I get it!!! thanks