Question

Help help needed for composition of function

Answer 1

Answer:

$\circledast \ \ f\circ f\left( x\right) = x$

$\circledast \ \ g\circ g\left( x\right) =4x - 21$

Step-by-step explanation:

$f(x)=\frac{5}{2x}$

g(x) = 2x - 7

==============

$f\circ f\left( x\right) =\frac{5}{2\left( f\left( x\right) \right) }$

             $=\frac{5}{2\left( \frac{5}{2x} \right) }$

             $=\frac{5}{\left( \frac{5}{x} \right) }$

             $=5\times\frac{x}{5}$

             $=x$

_____________

$g\circ g\left( x\right) =2(g(x)) - 7$

            = 2(2x - 7) - 7

           = 4x - 14 - 7

           = 4x - 23