Question

1 (3x+5x)
2 (4x+7)x(3x²-2x+3)
3 (4x-3y-1)x(2x-y+3)

Answer 1

1.8x
2.(4x)(3x²-2x+3)
=12x³+8x²+12x
(7)(3x²-2x+3)
=21x²-14x+21
maka(4x+7)×(3x²-2x+3)=12x³+8x²+12x+21x²-14x+21=12x³+8x²+21x²+12x-14x+21=12x³+29x²-2x+21
3.(4x)(2x-y+3)=8x²-4xy+12x
(-3y)(2x-y+3)=-6xy+3y²-9y
(-1)(2x-y+3)=-2x+y-3
maka(4x-3y-1)×(2x-y+3)=8x²-4xy+12x-6xy+3y²-9y-2x+y-3
=8x²+3y²-4xy-6xy+12x-2x-9y+y-3
=8x²+3y²-10xy+10x-8y-3