Question

resolva as equações do 2° grau em z.

b) 6x²-5x+1=0

c) x²+3x-4=0

Answer 1

Explicação passo-a-passo:

$b) \: 6 {x}^{2} - 5x + 1 = 0 \\ x = \frac{ - ( - 5) + - \sqrt{ {( - 5)}^{2} - 4 \times 6 \times 1 } }{2 \times 6} \\ \\ x = \frac{5 + - \sqrt{25 - 24} }{12} \\ \\ x = \frac{5 + - \sqrt{1} }{12} \\ \\ x 1= \frac{5 + 1}{12} = \frac{6}{12} = \frac{1}{2} \\ \\ x2 = \frac{5 - 1}{12} = \frac{4}{12} = \frac{1}{3} \\ \\ \\ c) \: {x}^{2} + 3x - 4 = 0 \\ x = \frac{ - 3 + - \sqrt{ {3}^{2} - 4 \times 1 \times ( - 4) } }{2 \times 1} \\ \\ x = \frac{ - 3 + - \sqrt{9 + 16} }{2} \\ \\ x = \frac{ - 3 + - \sqrt{25} }{2} \\ \\ x1 = \frac{ - 3 + 5}{2} = \frac{2}{2} = 1 \\ \\ x2 = \frac{ - 3 - 5}{2} = \frac{ - 8}{2} = - 4$