Вправи: 826 (1-3)

826. Виконайте дії:

1) x+23x+9 – 4-x5x+15 = x+ 2\53(x+3) – 4- x\35(x+3) = 5x+2- 3(4-x)5(x+3) = 5x+10-12+3x15(x+3) = 8x-215x+45;

2) m+ 1\m+3m-3 – m+ 2\m-3m+3 = m+1m+3- (m+2)(m-3)m-3(m+3) = m2+ m+3m+3-(m2+ 2m-3m-6)m-3(m+3) = m2+ 4m+3- m2+ m+6m-3(m+3) = 5m+9m-3(m+3);

3) xx+y – 2y2y2- x2 – yx-y = x\x-yx+y – 2y2x-y(x+y) – y\x+yx-y = xx-y+ 2y2- y(x+y)x-y(x+y) = x2- xy+2y2- xy- y2x-y(x+y) = x2- 2xy+ y2x-y(x+y) = (x-y)2x-y(x+y) = x-yx+y;

4) a+3a2- 2a – a-25a-10 + a+25a = a+ 3\5a(a-2) – a- 2\a5(a-2) + a+ 2\a-25a = 5a+3- aa-2+ (a-2)(a+2)5a(a-2) = 5a+15- a2+ 2a+ a2- 45a(a-2) = 7a+115a2- 10a;

5) 33(a-3) – a-12a2- 4a+2 = 33(a-3) – a-12(a-1)2 = 1\2a-3 – 12(a-1) = 2-12(a-1) = 12a-2;

6) 2 – 14m-2 – m = 2- m\m-21 – 14m-2 = -(m-2)2- 14m-2 = -m2- 4m+4- 14m-2 = -m2+ 4m-4-14m-2 = -m2+ 4m-18m-2.