# Thread: Calculus II Homework Problem

1. ## Calculus II Homework Problem

Not sure how to do this one, the way that it is worded confuses me. I'd appreciate any help you may offer.

Find an approximation for h(x)=e^(-x^2)) by finding a formula f(x) = e^x = p5(x), where p5(x) is a fifth degree polynomial, and by writing h(x) = f(-x^2) = p5(-x^2).

Thank you

2. Originally Posted by colonelone
Not sure how to do this one, the way that it is worded confuses me. I'd appreciate any help you may offer.

Find an approximation for h(x)=e^(-x^2)) by finding a formula f(x) = e^x = p5(x), where p5(x) is a fifth degree polynomial, and by writing h(x) = f(-x^2) = p5(-x^2).

Thank you
you should already know ...

$\displaystyle e^u = 1 + u + \frac{u^2}{2!} + \frac{u^3}{3!} + ...$

now find the desired polynomial approximation of $\displaystyle e^{-x^2}$

3. Originally Posted by skeeter
you should already know ...

$\displaystyle e^u = 1 + u + \frac{u^2}{2!} + \frac{u^3}{3!} + ...$

now find the desired polynomial approximation of $\displaystyle e^{-x^2}$
Where u = $\displaystyle {-x^2}$?

4. Originally Posted by colonelone
Where u = $\displaystyle {-x^2}$?
that's how it works