Taylor Polynomial of f(x) = x^3sin(x)

In summary, the problem is asking for the first 3 non-zero terms of the Taylor polynomial generated by the function f(x) = x^{3} sin(x) at the point a = 0. The relevant equation for finding the Taylor polynomial is f^{n}(x) * (x-a)^{n} / (n!), and at a=0, it becomes a Maclaurin series. The answer is found by multiplying the Taylor series for sin(x) by x^{3} and taking the first three non-zero terms, which are 0, x^{3}, and 0.
  • #1
november1992
120
0

Homework Statement



Find the first 3 non-zero terms of the Taylor polynomial generated by f (x) = [itex]x^{3}[/itex] sin(x) at a = 0.

Homework Equations


[itex]f^{n}[/itex](x) * [itex](x-a)^{n}[/itex] / (n!)

The Attempt at a Solution



I got the question wrong: my answer was 1/3! + 1/5! + 1/7!
Here is the answer below. I was wondering how my teacher got that answer. Do you have to do the product rule to find the derivatives?
sxjbfc.png
 
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  • #2
Do you know the Taylor series for ##\sin x\ ##? He just multiplied that by ##x^3##.
 
  • #3
november1992 said:

Homework Statement



Find the first 3 non-zero terms of the Taylor polynomial generated by f (x) = [itex]x^{3}[/itex] sin(x) at a = 0.

Homework Equations


[itex]f^{n}[/itex](x) * [itex](x-a)^{n}[/itex] / (n!)

The Attempt at a Solution



I got the question wrong: my answer was 1/3! + 1/5! + 1/7!
Here is the answer below. I was wondering how my teacher got that answer. Do you have to do the product rule to find the derivatives?
sxjbfc.png

The Taylor polynomial is a function of x. Your answer is really just a single number.

You wrote something in the relevant equation section. Do you know what it represents and what it's used for?

Your textbook undoubtedly has some examples that are like this problem. Have you looked at any of them?
 
  • #4
At a=0, it means that the function f(x) is approximated near the point x=a=0. In other words, you have a Maclaurin series. Adapt and use the relevant equation from your post #1.
 

Related to Taylor Polynomial of f(x) = x^3sin(x)

1. What is a Taylor polynomial?

A Taylor polynomial is a polynomial function that approximates a given function by using a specific point as a starting point and taking into account the function's derivatives at that point.

2. How is a Taylor polynomial calculated?

A Taylor polynomial is calculated using the Taylor series, which is a formula for finding the coefficients of the polynomial. The formula involves taking the derivatives of the function at the chosen point and plugging them into the formula.

3. What is the purpose of a Taylor polynomial?

The purpose of a Taylor polynomial is to approximate a function with a simpler polynomial function. This can be useful in situations where the original function is difficult to work with, but the polynomial is easier to manipulate.

4. Why is the Taylor polynomial of f(x) = x^3sin(x) useful?

The Taylor polynomial of f(x) = x^3sin(x) is useful because it provides a good approximation for the function near the chosen point. It can also be used to calculate values of the function at points that are close to the chosen point.

5. What is the difference between a Taylor polynomial and a Taylor series?

A Taylor polynomial is a finite polynomial function, while a Taylor series is an infinite sum of terms. The Taylor polynomial only takes into account a finite number of derivatives, while the Taylor series includes all derivatives of the function.

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