Question

ПРОШУ СДЕЛАйТЕ ТОЛЬКО ЭТО И ВСЕ СИЖУ НА К/Р

Answer 1

а) $\frac{x-y}{xy} +\frac{y-z}{yz} =\frac{z(x-y)}{xyz} +\frac{x(y-z)}{xyz} =\frac{xz-yz+xy-xz}{xyz} =\frac{xy-yz}{xyz} =\frac{y(x-z)}{xyz} =\frac{x-z}{xz}$

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

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

г) $\frac{c+6b}{ac+2bc-6ab-3a^{2}} +\frac{2b}{a^{2}+2ab} -\frac{b}{ac-3a^{2}} =\frac{c+6b}{a(c-3a)+2b(c-3a)} +\frac{2b}{a(a+2b)} -\frac{b}{a(c-3a)} =\frac{c+6b}{(a+2b)(c-3a)} +\frac{2b}{a(a+2b)} -\frac{b}{a(c-3a)} =\frac{a(c+6b)}{a(a+2b)(c-3a)} +\frac{2b(c-3a)}{a(a+2b)(c-3a)} -\frac{b(a+2b)}{a(a+2b)(c-3a)} =\frac{ac+6ab+2bc-6ab-ab-2b^{2}}{a(a+2b)(c-3a)} =\frac{ac+2bc-ab-2b^{2}}{a(a+2b)(c-3a)} =\frac{c(a+2b)-b(a+2b)}{a(a+2b)(c-3a)} =\frac{(c-b)(a+2b)}{a(a+2b)(c-3a)} =\frac{c-b}{a(c-3a)}$