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# Quick silly partial fractions. watch

1. Q/[W(Q-W)], Looking at it straight away I spot the answer is:
1/W + 1/(Q-W)

But when I went through the usual steps for finiding partial practions it just didn't work .
You know, the:

Q/[W(Q-W)] = A/W + B/(Q-W), :. Q = A(Q-W) + BW

Then I wrote a page of rubbish which didn't lead to the correct answer....
Anyone care to show me their workings out?
2. Hello....here's my working:

Q/W(Q-W) = A/W + B/(Q-W)

implies...

Q = A(Q-W) + BW

So equating Q's:
1 = A

Equating W's:
0 = -A + B ----> A = B --------> B = 1

So the expression is:
1/W + 1/(Q-W)

I'm interested to know how you could look at it straight away and spot that...I couldn't!
3. (Original post by Worzo)
Hello....here's my working:

Q/W(Q-W) = A/W + B/(Q-W)

implies...

Q = A(Q-W) + BW

So equating Q's:
1 = A

Equating W's:
0 = -A + B ----> A = B --------> B = 1

So the expression is:
1/W + 1/(Q-W)

I'm interested to know how you could look at it straight away and spot that...I couldn't!
lol, yea, thanks, there was a lil mistake which i failed to notice in my calculations. (which then got bigger as this is a part of a bigger quuestion, took me a while to narrow it down to this point. Thanks!)

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