Question

Suppose f(x)=√x+1 and g(x)=x² + n. If f(g(7)) = 9, what is the value of g(n)?
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Answer 1

Explanation:

g(7)=

`{7}^(2) + n`

`49 + n`

f(g(7))=n

`f(g(7)) = √(49 + n + 1)`

`f(g(7)) = √(n + 50)`

`9 = √(n + 50)`

`81 = n + 50`

`n = 31`

So

`g(31) = 31 {}^(2) + 31`

`= 992`