Вопрос:

37. Сократите дроби: а) \(\frac{2x+bx-2y-by}{7x-7y}\); б) \(\frac{8a+4b}{2ab+b^2-2ad-bd}\); в) \(\frac{xy-x+y-y^2}{x^2-y^2}\); г) \(\frac{a^2+2ac+c^2}{a^2+ac-ax-cx}\).

Ответ:

а) \(\frac{2x+bx-2y-by}{7x-7y}=\frac{(b+2)(x-y)}{7(x-y)}=\frac{b+2}{7}\).

б) \(\frac{8a+4b}{2ab+b^2-2ad-bd}=\frac{4(2a+b)}{b(2a+b)-d(2a+b)}=\frac{4(2a+b)}{(2a+b)(b-d)}=\frac{4}{b-d}\).

в) \(\frac{xy-x+y-y^2}{x^2-y^2}=\frac{x(y-1)-(y^2-y)}{(x-y)(x+y)}=\frac{(y-1)(x-y)}{(x-y)(x+y)}=\frac{y-1}{x+y}\).

г) \(\frac{a^2+2ac+c^2}{a^2+ac-ax-cx}=\frac{(a+c)^2}{a(a+c)-x(a+c)}=\frac{(a+c)^2}{(a+c)(a-x)}=\frac{a+c}{a-x}\).

Ответ: а) \(\frac{b+2}{7}\); б) \(\frac{4}{b-d}\); в) \(\frac{y-1}{x+y}\); г) \(\frac{a+c}{a-x}\).