Thread: tricky integration of a fraction

i am so confused as to what to do, someone please help!!

Originally Posted by wik_chick88

i am so confused as to what to do, someone please help!!

Use the method of partial fraction decomposition.

this is what i have:
\frac{1}{P(20000-P)} = \frac{A}{P} + \frac{B}{20000-P} (i brought the 200000 out the front of the integral)
= \frac{20000A - AP + BP}{P(20000-P)}
= \frac{20000A + (B-A)P}{20000-P}

equate coefficients:
20000A = 1, therefore A = \frac{1}{20000}
B - A = 0, therefore B = A = \frac{1}{20000}

therefore:
\frac{1}{P(20000-P)} = \frac{1}{20000P} + \frac{1}{20000(20000-P)}

have i gotten it right so far? i know where to go from here, as long as i havent made any mistakes!!

Originally Posted by wik_chick88

this is what i have:
\frac{1}{P(20000-P)} = \frac{A}{P} + \frac{B}{20000-P} (i brought the 200000 out the front of the integral)
= \frac{20000A - AP + BP}{P(20000-P)}
= \frac{20000A + (B-A)P}{20000-P}

equate coefficients:
20000A = 1, therefore A = \frac{1}{20000}
B - A = 0, therefore B = A = \frac{1}{20000}

therefore:
\frac{1}{P(20000-P)} = \frac{1}{20000P} + \frac{1}{20000(20000-P)}

have i gotten it right so far? i know where to go from here, as long as i havent made any mistakes!!

Correct.

It is correct, math tags?

oops forgot to wrap the text!

this is what i have:
(i brought the 200000 out the front of the integral)
=
=
equate coefficients:
20000A = 1, therefore A =
B - A = 0, therefore B = A =

therefore:

have i gotten it right so far? i know where to go from here, as long as i havent made any mistakes!!