Question

Знайдіть всі корені рівняння

Answer 1

$\displaystyle\bf\\1)\\\\5x^{2} -6x+1=0\\\\D=(-6)^{2} -4\cdot 5\cdot 1=36-20=16=4^{2} \\\\\\x_{1} =\frac{6-4}{10}=0,2\\\\\\x_{2} =\frac{6+4}{10}=1\\\\\\Otvet \ : \ 0,2 \ ; \ 1\\\\2)\\\\x^{2}-5x+4=0\\\\D=(-5)^{2} -4\cdot4=25-16=9=3^{2} \\\\\\x_{1} =\frac{5-3}{2} =1\\\\\\x_{2} =\frac{5+3}{2}=4\\\\\\Otvet: \ 1 \ ; \ 4\\\\3)\\\\2x^{2} -9x+10=0\\\\D=(-9)^{2} -4\cdot 2\cdot 10=81-80=1 \\\\\\x_{1} =\frac{9-1}{4}=2\\\\\\x_{2} =\frac{9+1}{4}=2,5$