# Error bound for Taylor's Expansion

Use Taylor's Theorem to approximate an upper bound for the error approximation.

Sinh$$(.9) \approx .9 + \frac{(.9)^3}{3!}$$.

From the formula,

$$R_4(x) \leq \frac{|.9|^5}{120}$$|cosh$$(.9)$$|. However, I'm getting the wrong answer. Am I missing something?

Any help appreciated.

• Can you elaborate on what you mean by "getting the wrong answer"? Plugging the values into the calculator shows that your error bound is indeed valid, and the math checks out. – Sohom Paul Jul 2 at 20:48
• I'm entering my answer into the program I submit my homework in, and it's saying it's incorrect. I cannot think of any reason why this might be – mXdX Jul 2 at 20:52
• Because it's not. You can email your teacher, but there's not much we can do here. – Simply Beautiful Art Jul 2 at 20:54
• Well, thanks for confirming this at the very least. – mXdX Jul 2 at 20:55