# Math Help - limit help!!

1. ## limit help!!

to prove that sine is continuous we need to show that limx--> sin(x)=sin(a) for every real number a. if we let h=x-a, then x=a+h and x-->a <--> h-->0. so an equivalent statement is that

limh-->0sin(a+h) = sin(a)

use the theorem:

limx-->0cos(x) = 1 and limx-->0sin(x)=0

to show that this is true.

2. ## Re: limit help!!

You are supposed to use the identity for the sine of a sum of angles and the theorems about the limit of the sum and product of functions.

3. ## Re: limit help!!

can you show me what you mean please?

4. ## Re: limit help!!

Look up the identities for cos(x+ y) and sin(x+y).

5. ## Re: limit help!!

Have you followed the link and found the formula? You need to rewrite sin(a+h). Also, do you know theorems about the limit of product and sum of functions?