**The question:**
Find a value for n such that the absolute error in the approximation

is less than

, given that

about 0.

(Note: f(x) = cos(x))

**My attempt:**
I replace sin(c) with 1, since it is an upper bound, and x with 2:

We want this error to be less that

, so:

This is equivalent to finding:

Why?! Of course that then you get what you get since the LHS is the power of a number greater than 2, whereas the RHS

is a **negative** power of a number greater than 1...! You forgot, or for some reason you

thought, that you can dismiss the LHS's denominator:

So I get .

Tonio
This isn't right. The answer should be n = 14. Where have I gone wrong? Thanks.