Question

ПОМОГИТЕ РЕШИТЬ!!!!!!!!

Answer 1

1)$frac{a+b}{5} - frac{a}{5}= frac{a+b-a}{5}= frac{b}{5}$
2) $frac{m-n}{a}+ frac{m+n}{a} = frac{m-n+m+n}{a} = frac{2m}{a}$
3) $frac{ a^{2} }{a+b} - frac{ b^{2}}{a+b} = frac{ a^{2} - b^{2} }{a+b}= frac{(a+b)(a-b)}{a+b}=a-b$
4) $frac{ c^{2} + d^{2}}{c-d} - frac{2cd}{c-a} = frac{ c^{2} + d^{2}-2cd }{c-a} = frac{ c^{2} -2cd+ d^{2} }{c-a} = frac{(c-a)^{2} }{c-a}=c-a$
5)$frac{x}{ x^{2} - y^{2} } - frac{y}{x^{2} - y^{2}} = frac{x-y}{ x^{2} - y^{2} } = frac{x-y}{(x+y)(x-y)}= frac{1}{x+y}$