let f : N -> R be a function such that f((x)=4x^{2}+12x+15.Show that f :N -> S,where S is the range of f,is invertible.Also find f ^{-1}.

to show that function is invertible. we will show that function is one-one and onto.

the given function is:

let

such that

thus therefore function is one-one.

the function f is onto if there exist x in N such that f(x)=y

hope this helps you.

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