Question

Dada a função do 2 grau f(X) = X²-7X + 12. Determine
X= 7
X = 8×9
X= 81
​

Answer 1

$\large\sf{} \blue{f(x) = {x}^{2} - 7x + 12}$

Vamos lá:

$\large\sf{}f(7) = {7}^{2} - 7 \times 7 + 12 \\ \large\sf{}f(7) = 49 - 7 \times 7 + 12 \\ \large\sf{}f(7) = 49 - 49 + 12 \\ \large\sf{}f(7) = 0 + 12 \\ \red{\large\sf{}f(7) = 12}$

$\large\sf{}f(72) = {72}^{2} - 7 \times 72 + 12 \\\large\sf{}f(72) = 5184 - 7 \times 72 + 12 \\ \large\sf{}f(72) = 5184 - 504 + 12 \\\large\sf{}f(72) = 4680 + 12 \\ \orange{ \large\sf{}f(72) = 4692}$

$\large\sf{}f(81) = {81}^{2} - 7 \times 81 + 12 \\ \large\sf{}f(81) = 6560 - 7 \times 81 + 12 \\ \large\sf{}f(81) = 6560 - 564 + 12 \\ \large\sf{}f(81) = 5996 + 12 \\ \pink{ \large\sf{}f(81) = 6008}$

${\large\boxed{\boxed{  { \large \sf Bons~Estudos }}}}$