Вправи: 308

308. Спростіть вираз.

a) (xy2 – 1x) : (1x + 1y) = x2- y2xy2 : x+yxy = (x2- y2)xyxy2(x+y) = (x-y)y;

б) (ab + a2b2) : (b2a2 + ba) = ab+a2b2 : b2+ aba2 = ab+a•a2b2b+ab = a3b3;

в) (mm+1 + 1) : (1 – 3m21-m2) = m+m+1m+1 : 1- m2- 3m21-m2 = 2m+1m+1 • 1-m21-4m2 = 1-m1-2m;

г) (3a+13a-1 – 3a-13a+1) : 12a15a-5 = (3a+1)2- (3a-1)29a2- 1 • 5(3a-1)12a = 3a+1-3a+13a+1+3a-1•5(3a-1)3a-13a+1•12a = 5 •2 •6a12a(3a+1) = 53a+1.