a) (x+2)(2x-1)=2x²+3x-2
b)(2-y)(y²+3)=2y²+6-y³-3y= -y³+2y²-3y+6
v)a(a+4)-(a-2)(a+6)=a²+4a-(a²+6a-2a-12)=a²+4a-(a²+4a-12)=a²+4a-a²-4a+12=12
g) (1-3p)(9p²+3p+1)=9p²+3p+1-27p³-9p²-3p=1-27p³
2. a) ab+2b+ac+2c=b(a+2)+c(a+2)=(a+2)(b+c)
b) 9-3y+3x-xy=3(3-y)+x(3-y)=(3-y)(3+x)
a) (x+2)(2x-1)=2x²+3x-2
b)(2-y)(y²+3)=2y²+6-y³-3y= -y³+2y²-3y+6
v)a(a+4)-(a-2)(a+6)=a²+4a-(a²+6a-2a-12)=a²+4a-(a²+4a-12)=a²+4a-a²-4a+12=12
g) (1-3p)(9p²+3p+1)=9p²+3p+1-27p³-9p²-3p=1-27p³
2. a) ab+2b+ac+2c=b(a+2)+c(a+2)=(a+2)(b+c)
b) 9-3y+3x-xy=3(3-y)+x(3-y)=(3-y)(3+x)