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# C3 help number two. Watch

1. As I predicted, I'm well on the way to asking a whole heap of questions about C3. This time I'm having difficult with functions:

f(x)=x-2
g(x)=5/(x+2)

h=fg

so
a) find h(x)
b) find h^-1

I got h(x) to be 5/(x+2) -2 and x can't equal -2, however I then couldn't do part b) as I kept ending up with either an xy or an x/y when trying to get y by itself.

2. (y+2)(x+2)=5

x+2=5/(y+2)

....
3. (Original post by mathz)
(y+2)(x+2)=5

x+2=5/(y+2)

....
And with hindsight, it's actually really obvious...

Thanks though, fancy sitting the exam with me and pointing out all the things I miss?

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Updated: September 23, 2012
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