Is this proof by induction set out well?

Just wanted to check that this proof is set out correctly and that the last statement is logically correct:

Question

Quote:

Use mathematical induction to prove that

is divisible by 15 for all positive integers n.

Answer

Quote:

Let

be

is divisible by 15.

Assuming

to be true [1] (

),

From [1],

Therefore if

is divisible by 15, then so is

,

When

,

. Therefore the basis case holds true.

Therefore by mathematical induction,

Re: Is this proof by induction set out well?

Re: Is this proof by induction set out well?

That seems more clear thanks. Would you advise against writing is symbolically?

btw, I think you have to change the tags in your sig.

Re: Is this proof by induction set out well?

Re: Is this proof by induction set out well?

Quote:

Originally Posted by

**alexgeek** Would you advise against writing is symbolically?

Good question. See an example of a proof on p. 9 of "Mathematical Writing" by Knuth, Larrabee, and Roberts (PDF).

Re: Is this proof by induction set out well?

I was like ooh that looks interesting then saw that it's 112 pages long. I'll keep it until next week when my exams are over.

Thank you though.

Edit. Oh you said page 9. Brain is melting from too much maths sorry

Re: Is this proof by induction set out well?