1) а-m + ma = a-m + ma = 2(a-m)(a-m)+ ma= ⇒
2a+2m a²-m² 2(a+m) (a-m)(a+m) (a-m)(a+m)
⇒ 2a²-2am-2am+2m²+ma = 2a²+2m²-3am
(a-m)(a+m) (a-m)(a+m)
2) 2a²+2m²-3am · a-m = 2a²+2m²-3am
(a-m)(a+m) 3m 3m(a+m)
3) a² - 2a²+2m²-3am = a² -4a²-4m²+6am = -3a²-4m²+6am
6m (a+m) 3m(a+m) 6m(a+m) 6m(a+m)