Срочно нужно. Помогите

3.
$........=\frac{15(2-m)+12(m-3)}{((m+2)(2-m)(m-3)}= \frac{30-15m+12m-36}{((2+m)(2-m)(m-3)}= \frac{-6-3m}{(2+m)(2-m)(m-3)}=$ $\frac{-3(2+m)}{(2+m)(2-m)(m-3)}= \frac{-3}{(2-m)(m-3)}$
ответ Р
4.
$.....= \frac{2(2-x)+ x^{2}-2x}{x(x-2)(2-x)}= \frac{4-2x+ x^{2}-2x}{x(x-2)(2-x)}= \frac{(x-2)(x-2)}{x(x-2)(2-x)}= \frac{x-2}{2 x^{2}- x^{2} }$

5.
$.........= \frac{2b(2b+c)-4b^{2} }{(2b+c)(2b+c)}= \frac{4b^{2}+2bc-4b^{2}}{(2b+c)(2b+c)}= \frac{2bc}{(2b+c)^{2} }$
ответ А