Вправи: 151

151. Спростіть вираз:

1) a-b7a : a-b7b = a-b • 7b7a • (a-b) = ba;

2) x2- y2x2 : 6x+6yx5 = x-yx+y • x5x2 • 6 • (x+y) = x3(x-y)6 = x4- x3y6;

3) c-5c2- 4c : c-55c-20 = c-5 • 5(c-4)cc-4•(c-5) = 5c;

4) x-yxy : x2- y23xy = x-y•3xyxyx-y(x+y) = 3x+y;

5) a2- 25a+7 : a-5a+7 = a-5a+5(a+7)a+7(a-5) = a+51 = a + 5;

6) a2- 4a+4a+2 : (a – 2) = (a-2)2 • 1a+2(a-2) = a-2a+2;

7) (p2- 16k2)1 : p+4kp = p-4kp+4k• p1 • (p+4k) = p(p – 4k) = p² – 4pk;

8) a2- aba2 : a2- 2ab+ b2ab = aa-baba2(a-b)2 = ba-b.