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# Inverse funtion help please. :) C3 Watch

1. Hello there,

Could someone tell me if the inverse for the funtion:-

f(x) = 1 - 2/(3x^2+2) is correct please.

(x)(3y^2+2) = 1 - 2
3y^2+2 = -1/x
3y^2 = (-1/x) - 2
y^2 = [(-1/x) - 2]/3 If this is correct so far can I simplify it any further before square rooting? Also how do I chose between the + or - answer for the inverse?

Thanks! :0
2. For the +ve and -ve answers it would be both.
3. (Original post by apo1324)
Hello there,

Could someone tell me if the inverse for the funtion:-

f(x) = 1 - 2/(3x^2+2) is correct please.

(x)(3y^2+2) = 1 - 2
3y^2+2 = -1/x
3y^2 = (-1/x) - 2
y^2 = [(-1/x) - 2]/3 If this is correct so far can I simplify it any further before square rooting? Also how do I chose between the + or - answer for the inverse?

Thanks! :0
If you think then your work is wrong.
Let f(x)=y you need
to get get the inverse function
change x with y and will get y=f^(-1)(x)

and so on

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