Answer:
[tex]\Large \boxed{\sf \ \ f^{-1}(x)=x^2-3 \ \ }[/tex]
Step-by-step explanation:
Hello,
[tex]\text{For }x+3\geq 0\\\\f(x)=\sqrt{x+3}\\\\x=(fof^{-1})(x)=f(f^{-1}(x))=\sqrt{f^{-1}(x)+3}\\\\\text{*** take the square ***}\\\\f^{-1}(x)+3=x^2\\\\\text{*** subtract 3 from both sides ***}\\\\\large \boxed{\sf \ \ f^{-1}(x)=x^2-3 \ \ }\\[/tex]
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