Вправи: 175 (1)

175. Спростіть вираз:

1) a- a2a+1a- aa+1 = a\a+11- a2a+1a\a+11- aa+1 = aa+1- a2a+1 : aa+1- aa+1 = a2+ a- a2a+1 : a2+ a-aa+1 = a a+1 • a+1a2 = a(a+1)(a+1)a2 = 1a;

2) a- 6a-9a1- 3a = a\a1- 6a-9a1\a1- 3a = a2- (6a-9)a : a-3a = a2- 6a+9a : a-3a = (a-3)2 • aa • (a-3) = a – 3;

3) 11- 11+ 1a = 11- 1a+1a = 11\a+1- aa+1 = 1a+1-aa+1 = 1: 1a+1 = a + 1;

4) 2a-bb+ 1\b 2a+bb- 1\b = 2a-b+bb : 2a+b-bb = 2ab : 2ab = 1.