Note: `f@g(x) = f(g(x))`
This means, where you used to see an "x" in the equation for f(x), now plug in "g(x)"
To find `f^(-1)(x)`
First start with your equation, then switch the x and the y, then solve for y.
So for example:
`f(x)=4x+3`
Think of this as: `y=4x+3`
To find the inverse, switch the x and the y:
`x=4y+3`
Then solve for y
`y=(x-3)/4`
With this in mind, start with the first pair of functions:
`f(x)=x-2`
`g(x)=x^2`
`f@g(x)=x^2-2`
`(f@g)^(-1)(x)=sqrt(x+2)`
`f^(-1)(x)=x+2`
`g^(-1)(x)=root()(x)`
`f^(-1) @ g^(-1) (x) = root()(x)+2`
`g^(-1)@f^(-1)(x)=root()(x+2)`
So, at least in this case,
`(f@g)^(-1)(x)=g^(-1)@f^(-1)(x)`
Do the same for the second set of equations:
`f(x)=(1)/(x)+1`
`g(x)=3x-2`
`f@g(x)=(1)/(3x-2)+1`
`(f@g)^(-1)(x)=``((1)/(x-1)+2)/(3)=(2x-1)/(3(x-1)`
` `
` `
`f^(-1)(x)=(1)/(x-1)`
`g^(-1)(x)=(x+2)/(3)`
`f^(-1)@g^(-1)(x)=(1)/((x+2)/(3)-1)=(1)/((x-1)/(3))=(3)/(x-1)`
`g^(-1)@f^(-1)(x)=((1)/(x-1)+2)/(3)=((2x-1)/(x-1))/3=(2x-1)/(3(x-1)`
` `
So again, we have:
`(f@g)^(-1)(x)=g^(-1)@f^(-1)(x)`
PS: We have only shown
` (f@g)^(-1)(x)=g^(-1)@f^(-1)(x) `
is true for these pairs of functions, but it is always true
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