Question

70 балів ! поможіть будьласкаа!
квадратні рівняння 8 клас​

Answer 1

$\displaystyle\bf\\\frac{3}{x+1} +\frac{2x}{x-1} -\frac{3x+1}{x^{2} -1} =0\\\\\\\frac{3}{x+1} +\frac{2x}{x-1} -\frac{3x+1}{(x-1)(x+1)} =0\\\\\\\frac{3\cdot(x-1)+2x\cdot(x+1)-3x-1}{(x-1)(x+1)} =0\\\\\\\frac{3x-3+2x^{2} +2x-3x-1}{(x-1)(x+1)}=0\\\\\\\frac{2x^{2} +2x-4}{(x-1)(x+1)} =0\\\\\\x-1\neq 0 \ \ \Rightarrow \ \ x\neq 1\\\\x+1\neq 0 \ \ \Rightarrow \ \ x\neq-1\\\\2x^{2} +2x-4=0 \ |:2\\\\x^{2} +x-2=0\\\\D=1^{2} -4\cdot(-2)=1+8=9=3^{2}$

$\displaystyle\bf\\x_{1} =\frac{-1-3}{2} =\frac{-4}{2} =-2\\\\\\x_{2} =\frac{-1+3}{2} =\frac{2}{2} =1-neyd\\\\Otvet \ : \ -2$