Question

Решите графически уравнение: расписать по подробнее а) х^2=1 б) x^2=2x в)x^2=x+6 г)x^2=2x+3

Answer 1

$1) x^{2} =1\\ x^{2} -1=0\\(x-1)(x+1)=0\\x-1=0\\x=1\\x+1=0\\x=-1 \\$
$2) x^{2} =2x\\ x^{2} -2x=0\\x(x-2)=0\\x=0\\x-2=0\\x=2$
$3) x^{2} -x-6=0\\D=1+24=25\\ \sqrt{D} =5\\ x_{1} = \frac{1+5}{2} =3\\ x_{2} = \frac{1-5}{2} =-2$
$4) x^{2} -2x-3=0\\D=4+12=16\\ \sqrt{D} =4 \\ x_{1} = \frac{2+4}{2} =3\\ x_{2} = \frac{2-4}{2} =-1$