Question

Решите пожалуйсто В-2,4.

 

Answer 1

$y+frac{3y}{y-3}=frac{y^2-3y+3y}{y-3}=frac{y^2}{y-3}$

$frac{4}{x+4}-frac{x}{x-4}=frac{4(x-4)-x(x+4)}{(x+4)(x-4)}=\\ frac{4x-16-x^2-4x}{x^2-4^2}=frac{-16-x^2}{x^2-16}=-frac{x^2+16}{x^2-16}$

$frac{2}{x-5}+frac{x+5}{5x}=frac{10x+x^2-25}{5x(x-5)}=frac{x^2+10x-25}{5x^2-25x}$

$frac{2p-q}{p^2+qp}+frac{p-2q}{pq+q^2}=frac{2p-q}{p(p+q)}+frac{q-2p}{q(p+q)}=\\ frac{2pq-q^2+pq-2p^2}{pq(p+q)}=frac{3pq-q^2-2p^2}{pq(p+q)}$

$m-n+frac{4mn}{m-n}=frac{m^2-2mn+n^2+4mn}{m-n}=\\ frac{m^2+2mn+n^2}{m-n}=frac{(m+n)^2}{m-n}$

$frac{p-1}{p+2}-frac{p+1}{p-2}=\\ frac{p^2-2p-p+2-p^2-2p-p-2}{(p+2)(p-2)}=-frac{6p}{p^2-4}$

$frac{2}{x-y}+frac{x-y}{xy}=frac{2xy+x^2-2xy+y^2}{xy(x-y)}=\\ frac{x^2+y^2}{xy(x-y)}$

$frac{8m-n}{mn-m^2}-frac{m-8n}{mn-n^2}=frac{8m-n}{m(n-m)}+frac{m-8n}{n(n-m)}=\\ frac{8mn-n^2+m^2-8nm}{mn(n-m)}=frac{m^2-n^2}{mn(n-m)}=-frac{m+n}{mn}$

Answer 2

Надеюсь будет понятно....