Question 1169781

{{{f(x)=x+21}}}
 
{{{f^-1(x)}}} -> inverse

{{{f(x)=y}}}

{{{y=x+21 }}}swap variables

{{{x=y+21}}} ...solve for {{{y}}}

{{{x-21=y }}}

=> {{{f^-1(x) =x-21}}}


Find {{{f^-1(5)}}}

{{{f^-1(5) =5-21}}}

{{{f^-1(5) =-16}}}

{{{ graph( 600, 600, -25, 25, -25, 25, x+21, x-21) }}}