Explicație pas cu pas:
[tex]f(x) = x² + ax +4[/tex]
[tex]f( - 2) = 1 \\ = > ( - 2)^{2} + a( - 2) + 4 = 1 \\ 4 - 2a + 4 = 1 \\ 2a = 7 = > a = \frac{7}{2} [/tex]
[tex]f(a) = {a}^{2} + a \times a + 4 = 2 {a}^{2} + 4[/tex]
[tex]f(\frac{7}{2} ) = 2 ({\frac{7}{2} })^{2} + 4 = \frac{2 \times 49}{4} + 4 = \frac{49}{2} + 4 = \frac{49 + 8}{2} = \frac{57}{2} [/tex]
