Question

помогите решить уравнения , номер 2

Answer 1

$1) \ \dfrac{2y-7}{y^{2} -9} -\dfrac{y-10}{y^{2} -9}= \dfrac{2y-7-y+10}{y^{2}-9 } =\dfrac{y+3}{(y+3)(y-3)} =\dfrac{1}{y-3} \\\\\\y=3,1\\\\\\\dfrac{1}{y-3} =\dfrac{1}{3,1-3}=\dfrac{1}{0,1} =10\\\\\\y=-2\\\\\\\dfrac{1}{y-3} =\dfrac{1}{-2-3} =-\dfrac{1}{5} =-0,2$

$2) \ -\dfrac{3c-5}{4-c^{2} } +\dfrac{3-2c}{c^{2} -4} =\dfrac{3c-5}{c^{2} -4} +\dfrac{3-2c}{c^{2}-4 } =\dfrac{3c-5+3-2c}{c^{2}-4 } =\\\\\\=\dfrac{c-2}{(c-2)(c+2)} =\dfrac{1}{c+2} \\\\\\c=3\\\\\\\dfrac{1}{c+2}=\dfrac{1}{3+2}=\dfrac{1}{5} =0,2\\\\\\c=-3\\\\\\\dfrac{1}{c+2} =\dfrac{1}{-3+2} =-1$