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# Maths question functions watch

1. I have done the question, im just not sure about it, here it is.

The functions f and g are defined with their respective domains by:
f(x)=x-1 for all real values of x
g(x)=6/x+3 for all real values of x, x cannot equal -3

the composite function fg is defined by h

a) Find h(x) i got (6/x+3)-2

b)i) Find h^-1(x), where h^-1 is the inverse of h and then find the range.

This is the question im not sure about, i got the answer h^-1(x)= -3x/x+2
2. (Original post by harrybo6)
I have done the question, im just not sure about it, here it is.

The functions f and g are defined with their respective domains by:
f(x)=x-1 for all real values of x
g(x)=6/x+3 for all real values of x, x cannot equal -3

the composite function fg is defined by h

a) Find h(x) i got (6/x+3)-2

b)i) Find h^-1(x), where h^-1 is the inverse of h and then find the range.

This is the question im not sure about, i got the answer h^-1(x)= -3x/x+2
h(x) = 6/x + 1

y = 6/x + 1

x = 6/y + 1

etc
3. (Original post by the bear)
h(x) = 6/x + 1

y = 6/x + 1

x = 6/y + 1

etc
how did you get h(x)=6/x +1?
4. you may need to put more brackets in to your expression for g(x):

either fg(x) = 6/x + 3 -1

or fg(x) = 6/( x + 3 ) -1

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Updated: October 18, 2015
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