SOLUTION: Help me please!!! I need to express each difference in simpest form. ((d^(2)+3) / (d^(2) - 2d)) - ((d - 4) / (d)) and ((d^(2)-11) / (d^(2) - 7d +12)) - ((d+1) / (d-4))

Algebra ->  Rational-functions -> SOLUTION: Help me please!!! I need to express each difference in simpest form. ((d^(2)+3) / (d^(2) - 2d)) - ((d - 4) / (d)) and ((d^(2)-11) / (d^(2) - 7d +12)) - ((d+1) / (d-4))      Log On


   



Question 73004: Help me please!!!
I need to express each difference in simpest form.
((d^(2)+3) / (d^(2) - 2d)) - ((d - 4) / (d))
and
((d^(2)-11) / (d^(2) - 7d +12)) - ((d+1) / (d-4))

Answer by rmromero(383) About Me  (Show Source):
You can put this solution on YOUR website!

I need to express each difference in simpest form.

This problem is a RAtional expression. To subtract, we have to make sure
that the denominators are the same. If not, we will find the LCD.


d^2+3 d - 4
_________ - _______
d^2 - 2d d

d^2 + 3 d - 4
_________ - _______ LCD is d(d - 2)
d(d - 2) d
Make an equivalent expression using the LCD
d^2 + 3 (d - 4)(d - 2)
________ - _______________
d(d - 2) d(d - 2)

d^2 + 3 d^2 - 6d + 8
________ - _______________ Subtract the numerator, copy the denominator
d(d - 2) d(d - 2)

d^2 + 3 - (d^2 - 6d + 8)
__________________________
d (d - 2)

d^2 + 3 - 1(d^2 - 6d + 8)
__________________________
d (d - 2)
d^2 + 3 - d^2 + 6d - 8)
__________________________ Combine like terms
d (d - 2)

6d - 5
________
d(d -2)


and

d^2 - 11 d + 1
______________ - _________
d^2 - 7d +12 d - 4

d^2 - 11 d + 1
______________ - _________ Factor d^2 - 7d +12
(d - 3)(d - 4) d - 4

d^2 - 11 (d + 1)(d - 3)
______________ - ________________ Find equivalent expression using LCD
(d - 3)(d - 4) (d - 3)(d - 4)

d^2 - 11 (d^2 - 2d - 3)
______________ - ________________
(d - 3)(d - 4) (d - 3)(d - 4)

d^2 - 11 - (d^2 - 2d - 3)
____________________________
(d - 3)(d - 4)

d^2 - 11 - 1(d^2 - 2d - 3)
____________________________
(d - 3)(d - 4)

d^2 - 11 - d^2 + 2d + 3)
____________________________ Combine like terms
(d - 3)(d - 4)

2d - 8
_______________ Factor 2d - 8.
(d - 3)(d - 4)

2(d - 4)
_______________ Divide the common factor.
(d - 3)(d - 4)

2 cross%28d+-+4%29
_______________
(d - 3) cross%28d+-+4%29

2
_______
d - 3