Вправи: 744

744. Скоротіть дріб:

1) 3+ 323 = (3)2+ 323 = 3(3+1)23 = 3+12;

2) 5-5 10-52 = (5)2 -5 52-(5 )22 = 5(5-1)5 • 2(1-5) = 5-1-2(5-1) = –12;

3) 2-66-3 = (2)2-2 • 3 2 • 3-(3 )2 = 2(2- 3)3(2- 3) = 23 = 63;

4) 4a-22a+2 = (2a-2)(2a+2) (2a+ 2) = 2a – 2;

5) 9a- b29a+6ba+ b = (3a- b)(3a+ b)(3a+ b )2 = 3a- b3a+ b;

6) aa-8a+2a+4 = (a )2- 23a+2a+4 = (a-2)(a+2a+4)(a+2a+4 = a – 2.