factoring!! Flashcards
1
Q
(a+b)^2 =
A
a^2+2ab+b^2
2
Q
(a-b)^2=
A
a^2-2ab+b^2
3
Q
a^2-b^2=
A
(a-b)(a+b)
4
Q
a^2+b^2
A
(a+ib)(a-ib)
5
Q
a^3-b^3
A
(a-b)(a^2+ab+b^2)
6
Q
a^3+b^3
A
(a+b)(a^2-ab+b^2)
7
Q
(a+b+c)^2
A
a^2+b^2+c^2+2ab+2bc+2ac
- applies to > than 2 terms!!
- legit just keep combining (a^2+b^2+c^2+d^2+2ab+2bc+2ac+2ad+2db+2dc)
8
Q
sign rules for a^2 +/ 2ab +/- b^2
A
• first sign: if positive, positive sign is with the bigger factor
if negative, negative sign is with the smaller factor
• second sign: if positive, factors will have the same signs
9
Q
a(b+c)-d(b+c)=
A
(b+c)(a-d)
