f(x)=x^2 -7 +7 y+7=x^2 sqrt sqrt(y+7)=x swap sqrt(x+7)=y f^-1(x) = sqrt(x+7) Domain whatever is under the sqrt must be grather or equal to 0 x+7>_0 -7 x>_-7 if asking for set notai {xIx>_-7} f(f^-1(x)) = f(sqrt(x+7))\ now import the original question where ^2 and -7 come from = sqrt(x+7))^2 - 7 sqrt and squared cancel ouy =x+7-7 =X Second check import the og question F^-1(f^(x))=F^-1(x^2-7) importing answer = sqrt(x^2-7)+7 combine first cause its under Sqrt(x^2) =X IF DECIMAL MAKE FRACTION f(x) = x^3 =9 y-x^3 -9 3sqrt(y +9)= 3sqrt(x^3) 3Sqrt(y+9) = x swap 3Sqrt(x+9)= y f^-1(x) = 3sqrt(x+9) Domain {xI-infinity<x<+infinity} f(f^-1(x)) = f(3sqrt(x+9)) insert =3sqrt(x+9)^3 -9 =x+9-9 =x f^-1(x^3-9) Add answer =3sqrt(x^3-9)+9 =3sqrt(x^3) =X