JEE MATHEMATICS MCQ: FUNCTIONS

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Application +4 | -1

f:R \to R\;and\;g\;:R \to R

are defined by

f\left( x \right) = 2x + 3\;and\;g\left( x \right) = {x^2} + 7,

then the values of x such that

g\left( {f\left( x \right)} \right) = 8

are

View answer and explanation

Correct option: C

- 1,\; - 2

Option C (-1, -2) is correct because these are the solutions to the equation g(f(x)) = 8, found by substituting and solving the quadratic.

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