Вправи: 188

188. Виконайте множення виразів:

1) (x – 3) • 11x-3 = x-31 • 11x-3 = x-3•111 •(x-3) = 11;

2) (3x + 2) • (–22+3x) = 3x+21 • (–22+3x) = –3x+2•21 •(2+3x) = –2;

3) (2a – 1) • 51-2a = 2a-11 • 51-2a = 2a-1•51 •(1-2a) = –2a-1•5(2a-1) = –5;

4) (2x – 2) • 6x-1 = 2x-21 • 6x-1 = 2x-2•61 •(x-1) = 2x-1•6x-1 = 12;

5) (3a + 1) • 52+6a = 3a+11 • 52+6a = 3a+1•51 •(2+6a) = 3a+1•52(1+3a) = 52 = 2,5;

6) (ax – a) • 2x-1 = ax-a1 • 2x-1 = ax-a•21 •(x-1) = ax-1•2x-1 = 2a;

7) (ax + 2a) • ax+2 = ax+2a1 • ax+2 = ax+2•a1 •(x+2) = a²;

8) (3b – ab) • 32a-6 = 3b-ab1 • 32a-6 = 3b-ab•31 •(2a-6) = b3-a•32(a-3) = –ba-3•32 •(a-3) = –3b2.