Question

алгебра алгебраические дроби, заранее спасибо​

Answer 1

$\frac{c+3}{3} -\frac{5c}{3} =\frac{c+3-5c}{3} =\frac{3-4c}{3}$

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

$\frac{a+b}{a^{2}} +\frac{a-b}{ab} =\frac{ab+b^{2}}{a^{2}b} +\frac{a^{2}-ab}{a^{2}b} =\frac{ab+b^{2}+a^{2}-ab}{a^{2}b} =\frac{a^{2}+b^{2}}{a^{2}b}$

$\frac{5x+3y}{2(x+y)} -\frac{7x+4y}{3(x+y)} =\frac{3(5x+3y)}{6(x+y)} -\frac{2(7x+4y)}{6(x+y)} =\frac{15x+9y-14x-8y}{6(x+y)} =\frac{x+y}{6(x+y)} =\frac{1}{6}$

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