Вправи: 720

720. Скоротіть дріб:

1) 4a-16a2-16 = 4(a-4)(a-4)(a+4) = 4a+4;

2) 12b3-8b22-3b = 4b2(3b-2)-(3b-2) = –4b²;

3) c2+10c+255c+25 = (с+5)25(c+5) = c+55;

4) 4- m2m2- 4m+4 = 2-m(2+m)(m-2)2 = 2-m(2+m)(2-m)2 = 2+m2-m;

5) n3- n5n3- n = n3(1- n2)n(n2- 1) = -n2(n2- 1)n2- 1 = –n²;

6) 2-2x24x2- 8x+4 = 2(1- x2)4(x2- 2x+1) = 21-x(1+x)4(x-1)2 = 21-x(1+x)4(1-x)2 = 1+x2(1-x).