Вправи: 67

67. Спростіть вираз:

1) 3x-7y4xy + 15y-3x4xy = 3x-7y+15y-3x4xy = 8y4xy = 2x;

2) 7a+ p33p – 7a-2p33p = 7a+ p3- (7a-2p3)3p = 7a+ p3- 7a+2p33p = 3p33p = p²;

3) 5a- b46b5 – b4+ 5a6b5 = 5a- b4- (b4+ 5a)6b5 = 5a- b4- b4- 5a6b5 = -2b46b5 = –13b;

4) 3a-48a + 4a+58a – 1-a8a = 3a-4+4a+5-(1-a)8a = 7a+1-1+a8a = 8a8a = 1.