complex fraction: x/(x - 1) - x/(x + 2) - 8/(x^2 - 4)

R

rls4973

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Oct 30, 2008
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17
x - x - 8
-- --- ----
x-2 x+2 x^2-4

now i know to fact the x^2-4 and than make (x+2) (x-2) as my common than for the one that has x+2 I need to * by x-2 and the x-2 i need to * by x+2 but that is where I am getting stuck after that.
 
Re: another complex fraction

You have the denominator right. So your numerator will be:

x(x+2) - x(x-2) - 8

From there you'll just distribute and simplify.
 
Re: another complex fraction

this is what i got for that one

4x^2-8
-----------
(x-2)(x+2)

hope this is right thanks
 
Re: another complex fraction

rls4973 said:
this is what i got for that one

4x^2-8 <<<<<<<<< Incorrect
-----------
(x-2)(x+2)

hope this is right thanks
Click to expand...
 
once i got x(x=2) -x(x-2)-8 on top so that you will give u x^2=2x-X^2=2x-8 than my teacher said to combine like terms. am I missing a step?
 
rls4973 said:
once i got x(x=2) -x(x-2)-8 on top so that you will give u x^2=2x-X^2=2x-8 than my teacher said to combine like terms. am I missing a step?
Click to expand...
You are being careless - you are

mixing '+' sign with '=' sign and

mixing 'x' with 'X'

fix those and do the next step CAREFULLY.
 
sorry typo I am still getting the same answer

x(x+2)-x(x-2)-8
-------------------
(x-2)(x+2)

which when you simplify and combine like terms I am getting

x^2+2x-x^2+2x-8
---------------------
(x-2)(x+2)

than i get

4x^2-8
------------
(x-2)(x+2)
 
rls4973 said:
sorry typo I am still getting the same answer

x(x+2)-x(x-2)-8
-------------------
(x-2)(x+2)

which when you simplify and combine like terms I am getting

x^2+2x-x^2+2x-8 <<< Here you have '+x^2" and '-x^2' - they cancel out - how do you get 4x^2 in the step below?
---------------------
(x-2)(x+2)

than i get

4x^2-8
------------
(x-2)(x+2)
Click to expand...
 
rls4973 said:
2x+2x i wasn't sure if that should just be 4x or 4x^2
Click to expand...

2x + 2x = 2 times x plus 2 times x = 4 times x

2x times 2x = 2 times x times 2 times x = 2 times 2 times x times x = 4 times x^2
 
rls4973 said:
4x^2-8 is what i had above but someone told me it was wrong.
Click to expand...
Yes, because it is wrong, as the tutor explained and demonstrated. The fact that you don't seem to be aware of this suggests that you are probably needing extensive re-teaching on prerequisite material. :shock:

Please seriously consider hiring a qualified local tutor and setting aside an hour or two a day for intensive study sessions. With some luck and a lot of hard work, your tutor may be able to help you get caught up in only a few weeks.

Good luck! :D

Eliz.
 
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