Question

resolver a funçao de 2 grau f(x) = 3x²+9x-12

Answer 1

$3x {}^{2} + 9x - 12 = 0 \: ( \div 3) \\ x {}^{2} + 3x - 4 = 0 \\ 3 {}^{2} - 4 \times 1 \times ( - 4) \\ 9 + 16 \\ 25 \\ x = - 3 + - \sqrt{25 } \div 2 \times 1 \\ x = - 3 + - 5 \div 2 \\ x1 = - 8 \div 2 = - 4 \\ x2 = 2 \div 2 = 1$