`(2x+1)/(x-1)^2`
Since the denominator of the fraction is a repeated linear factor `(ax+b)^n` , its partial fraction decomposition is in the form:
`A_1/(ax+b) +A_2/(ax+b)^2+....+A_n/(ax+b)^n`
So,
`(2x+1)/(x-1)^2=A_1/(x-1)+A_2/(x-1)^2`
To determine the values of of A1 and A2, simplify the equation by multiplying both sides by the LCD of the three fractions.
`(x-1)^2((2x+1)/(x-1)^2)=(A_1/(x-1)+A_2/(x-1)^2)*(x-1)^2`
`2x+1=A_1(x-1)+A_2` (Let this be EQ1.)
Then, assign a value to x, such that A1 will be eliminated. And only A2 remains in the equation.
To do so, let x=1.
`2(1)+1=A_1(1-1)+A_2`
`2+1=A_1*0+A_2`
`3=A_2`
Now that value of A2 is known, plug-in this to EQ1.
`2x+1=A_1(x-1)+A_2`
`2x+1=A_1(x-1)+3`
`2x+1-3=A_1(x-1)+3-3`
`2x-2=A_1(x-1)`
Then, assign another value to x.
Let it be x=0.
`2(0)-2=A_1(0-1)`
`0-2=A_1(-1)`
`-2=-A_1`
`2=A_1`
Hence, ` (2x+1)/(x-1)^2=2/(x-1)+3/(x-1)^2` .
(For the second problem, kindly post it as a separate question in Homework Help.)
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