1.
а) x²-4xy+4y²
б) (1/16)m² - n²
2.
a) (6a-b)(6a+b)
б) (2-c)²
в) 3y³(5y²-1)
3.
((25.9-4.1)(25.9+4.1)):15=21.8*30:15=21.8*2=43.6
4.
c²-2cd+d²+5cd-d²=c²+3cd
(-2)²+3*(-2)*(1/3)=4-2=2
5.
a) ((1/3)k+p)((1/9)k² - (1/3)kp+p²)
б) (2c-8d²)(2c+8d²)
6.
x³-(8+x³)=x³-8-x³=-8
7.
(7-(x+5))(7+x+5)=0
(7-x-5)(7+x+5)=0
(2-x)(12+x)=0
1) 2-x=0
x=2
2) 12+x=0
x= -12
Ответ: -12; 2.