Question

1)решить уравнение x²-8x-2=2(x²-6)

Answer 1

$x^2-8x-2=2(x^2-6)\\ x^2-8x-2=2x^2-12\\ x^2-8x-2-2x^2+12=0\\ \\ -x^2-8x+10=0\\ D=b^2-4ac=(-8)^2-4*(-1)*10=64+40=\sqrt{104}\\ \\ x_1=\frac{-b+\sqrt{D} }{2a} =\frac{8+\sqrt{104}}{-2} =\frac{8+2\sqrt{26}}{-2}=-4-\sqrt{26}\\ x_2=\frac{-b-\sqrt{D} }{2a} =\frac{8-\sqrt{104}}{-2} =\frac{8-2\sqrt{26}}{-2}=-4+\sqrt{26}$