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# c4 expansion watch

1. Im getting the wrong answer ... doing something wrong obviously..

i need to expand

4/(1-X) - 4/(2+X)

For 4/(1-x)

i got 4(1-05X + 1/12 x^2) = 4-2x +1/3x^2

is that right?
if thats not, the rest wont be.
2. (Original post by cuddles x)
Im getting the wrong answer ... doing something wrong obviously..

i need to expand

4/(1-X) - 4/(2+X)

For 4/(1-x)

i got 4(1-05X + 1/12 x^2) = 4-2x +1/3x^2

is that right?
if thats not, the rest wont be.
Your coefficient of x is the wrong sign. The power is negative one times negative x results in a positive.
3. right... so then the expanison of the next one is :

4[2(1+05x)]^-1

=

(8+2x+1/6 x^2)

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