Вправи: 138

138. Спростіть вираз:

1) a-b3b • 3a-b = a-b • 33b(a-b) = 1b;

2) 2mn+ n26m • 2mn = nm2m+n • 2m6m • n = 2m+n3;

3) 7a+7bb6 • b3a+b = 7a+b • b3b6 • (a+b) = 7b3; 4) 32a • (a-3)a-3a+3 • 8a = 1a+3;

5) c-1c+6 • c+6c2- 2c+1 = c-1(c+6)c+6(c-1)2 = 1c-1;

6) m-2m2- 49 • m+7m-2 = m-2(m+7)m-7m+7(m-2) = 1m-7;

7) a+41 • a2a+8 = a+4 • a1 • 2(a+4) = a2;

8) x-94x+8 • x2+ 2xx-9 = x-9 • x(x+2)4x+2•(x-9) = x4;

9) 4a2- 4a+13a+3 • a+12a-1 = (2a-1)2 • (a+1)3a+1•(2a-1) = 2a-13;

10) a2- 254a • 4a2a2-5a = (a2- 25)aa2-5a = (a-5)(a+ 5)aa(a-5) = a + 5.