1. а) (3+а)(2а+1)=6а+3+2а^2+а=2а^2+
+7а+3
б) (5а+а^2)(3–2а)=15а–10а^2+3а^2–
–2а^3=15а–7а^2–2а^3
в) (3–х)(2–4х)=6–12х–2х+4х^2=4х^2
–14х+6
г) (–х–3)(2х–4)=–2х^2+4х–6х+12=
=12–2х^2–2х
2. а) 8–(2+а)(3а+4)=8–6а–8–3а^2–4а=–3а^2–10а
б) 2а^3+(а+а^2)(5–2а)=2а^3+5а–2а^2+5а^2–2а^3=5а+3а^2
в) (1–х)(2+2х)+(2–х)(1–2х)=2+2х–2х–
–2х^2+2–4х–х+2х^2=4–5х
г) (х–2)(х–5)–(х–3)(х–4)=х^2–5х–2х+
+10–х^2+4х+3х–12=-2
3. а) 3х(х–2)
б) (х–3)(х–8)
4. а) 3(х–4)+х^2–4х=3(х–4)+х(х–4)=
=(х–4)(3+х)
б) 2х–8–х(х–4)=2(х–4)–х(х–4)=(х–4)(2–х)
в) х^3+5х^2–2х–10=х^2(х+5)–2(х+5)
= (х+5)(х^2–2)
г) х^3–6х^2–2х+12=х^2(х–6)–2(х–6)
= (х–6)(х^2–2)