Вправи: 4.7

4.7 Подайте у вигляді дробу:

1) a4 + a-23 = 3a+4(a-2)12 = 3a+4a-812 = 7a-812;

2) 2x-y14 – x-y7 = 2x-y-2(x-y)14 = 2x-y-2x+2y14 = y14;

3) x-62x + 7-2y4y = 2yx-6+ x(7-2y)4xy = 2xy-12y+7x-2xy4xy = 7x-12y4xy;

4) 6m-n3m – 8n-5m4n = 4n6m-n- 3m(8n-5m)12mn = 24mn-4n2- 24mn+15m212mn = 15m2- 4n212mn.