Вправи: 98

98. Виконайте дії:

1) 1\ba(a+ b) + 1\ab(a+ b) = b+ aab(a+ b) = 1ab;

2) 4\b+2b – 8b(b+2) = 4(b+2)-8b(b+2) = 4b+8-8b(b+2) = 4bb(b+2) = 4b+2;

3) x\65(x+7) – x\56(x+7) = 6x-5x30(x+7) = x30x+210;

4) 4n+2\4 3(n-1) – 5n+3\3 4(n-1) = 44n+2-3(5n+3)12(n-1) = 16n+8-15n-912(n-1) = n-112(n-1) = 112.