Question

Let f : R → R, g : R → R be two functions defined by f(x) = x² + x + 1 and g(x) = 1 − x². Write fog (−2).

Answer 1

$$\begin{gathered} \left(fog\right)\left(-2\right)=f\left(g\left(-2\right)\right) \\ =f\left(1-{\left(-2\right)}^2\right) \\ =f\left(-3\right) \\ ={\left(-3\right)}^2+\left(-3\right)+1 \\ =9-3+1 \\ =7 \end{gathered}$$