The condition for the inverse function, f^(-1) to happen is function , f is one-one .(adsbygoogle = window.adsbygoogle || []).push({});

S0 consider this function , f(x)=x^2-5 , which is NOT a one-one function , and

f^(-1)=y

x=f(y)

x=y^2-5

y^2=x+5

[tex]f^{-1}(x)=\pm\sqrt{x+5}[/tex]

Seems that the inverse function of f exists without satisfying that condition .

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# Homework Help: Inverse function

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