Question

Розв’язати рівняння: 8x²-7x-1=0

Answer 1

$8x^2 - 7x - 1 = 0 \\ \\ D = 49 + 8 \cdot 4 = 49 + 32 = 81 = 9^2 \\ \\ x_1 = \dfrac{7 + 9}{16} = 1 \\ \\ x_2 = \dfrac{7 - 9}{16} = - \dfrac{2}{16} = -\dfrac{1}{8} \\ \\ OTBET: \ \boxed{x = -\dfrac{1}{8}; \ 1}$