Пошаговое объяснение:

а) (5х–2)(5х+2)–0,5(2х+3)²= (25х²–4)–0,5(4х²+12х+9)= (25х²–4)–(2х²+6х+4,5)= 25х²–4–2х²–6х–4,5= 23х²–6х–8,5

б) 6х–7–3(4х–1)(2–3х)= 6х–7–3(8х–12х²–2+3х)= 6х–7–(24–36х²–6+9х)= 6х–7–24+36х²+6–9х= 36х²–3х–25

№2

а) 4х–х³=х(4–х²)=х(2–х)(2+х)

б) –а²+2а–1=–(а–1)²= –(а–1)(а–1)

в) а²–б²+а–б= (а–б)(а+б)+(а–б)= (а–б)(а+б+1)