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You are not logged in. #1 20130319 05:26:40
Proof by induction questionHi, I am stuck on the last step. What am I supposed to do now? Last edited by genericname (20130319 05:30:38) #2 20130319 05:57:34
Re: Proof by induction question
If T(1) = 2 and if the proposed formula is as you've posted, then T(n) for n = 1 is 3^(11) = 3^(0) = 1, not 2. So the base step fails. #3 20130319 05:58:42
Re: Proof by induction questionhi genericname But you want T(1) = 2 ??? Let's see what is happening here. term to term rule: so if T(1) = 2 T(2) = 3x2 + 2 = 8 T(3) = 3x8 + 2 = 26 T(4) = 3x26 + 2 = 80 ........................ So did you mean Try again k=1 That's better. Now for the induction step assume use the term to term rule This has the right form, so the induction step is complete. Bob Last edited by bob bundy (20130319 06:03:25) You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #4 20130319 06:29:27
Re: Proof by induction questionOops, it was a typo. Sorry! It was supposed to be (3^n)1 like what Bob said. Last edited by genericname (20130319 06:29:47) #5 20130319 08:20:13
Re: Proof by induction questionIt's just a matter of multiplying out the bracket( by 3) Bob You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #6 20130319 15:38:32
Re: Proof by induction questionMultiplying out the bracket? Sorry, think I might be misunderstanding something, but wouldn't that be (9^(n1))  3 + 2 if you multiply by 3? Last edited by genericname (20130319 15:45:17) #7 20130319 18:13:02
Re: Proof by induction questionIf you times by another 3 you just increaase the power by 1 ie (n1) becomes n. Bob You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei 