Given the fraction (8x+14)/
(x+1)(x+5)
We need to rewrite into the form A/(x+1) +
B/(x+5)
==> (8x+14)/ (x+1)(x+5) = A/(x+1) +
B/(x+5)
We will rewrite with the common
denominator.
==> (8x+14)/(x+1)(x+5) = A(x+5)+
B(x+1)]/ (x+1)(x+5)
Now we will multiply by (x+1)(x+5) so
the denominator cancels.
==> 8x + 14 = A(x+5) +
B(x+1)
==> 8x + 14 = Ax + Bx + 5A +
B
==> 8x + 14 = (A+B)x +
(5A+B)
Now we will compare similar
terms.
==> A+B =
8............(1)
==> 5A+B = 14
........(2)
Now we will solve the
system.
We will subtract (1) from
(2).
==> 4A =
6
==> A = 6/4 =
3/2
==> A = 3/2
But
A+B= 8
==> B = 8- A = 8 - 3/2 =
13/2
==> B = 13/2
Now
we will substitute:
==> A/(x+1) + B(x+5) =
(3/2)/(x+1) +
(13/2)/(x+5)
= 3/2(x+2)
+ 13/2(x+5)
==> (8x+14)/(x+1)(x+5) =
3/2(x+1) + 13/2(x+5)
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