- #1

ivan77

- 17

- 0

## Homework Statement

what is the maclaurin series expansion of the function (1-x)^-2

## Homework Equations

maclaurin series

## The Attempt at a Solution

part of the solution is to find the n derivatives of the function to setup the series

MY ANSWERS

n f

^{n}(x)

0 (1-x)^-2 this should be the 0th derivative of the function

1 -2(1-x)^-3 this should be the first derivative of the function

2 6(1-x)^-4 second derivative

3 -24(1-x)^-5 third derivative

TEXTBOOK ANSWERS

n f

^{n}(x)

0 (1-x)^-2 this should be the 0th derivative of the function

1 2(1-x)^-3 this should be the first derivative of the function

2 6(1-x)^-4 second derivative

3 24(1-x)^-5 third derivative

NOTICE the lack of negatives on the 1 and 3 derivative.

The thing that is confusing the heck out of me as well is that when I look for the first derivative of the function (1-x)^-2 on wolfram alpha it gives me -2(1-x)^-3, but when I look for the maclaurin series, the answer does not show the negative sign.

Please help