Question

va rog e urgeenntttttttttttttttt cu tot cu explicatie,multumesc anticipat
1.(x-3)(x+2)+(2x+1)(3x-2)-2x(x+1)
(x-6)(2x+5)-(x+2)(x+3)+(3-x)(x+4)

Answer 1

(x-3)(x+2)+(2x+1)(3x-2)-2x(x+1)=(x²+2x-3x-6)+(6x²-4x+3x-2)-(2x²+2x)=x²-x-6+6x²-x-2-x²-2x=6x²-4x-8=2(3x²-2x-4)


(x-6)(2x+5)-(x+2)(x+3)+(3-x)(x+4)=(2x²+5x-12x-30)-(x²+3x+2x+6)+(3x+12-x²-4x)=(2x²-7x-30)-(x²+5x+6)+(12-x-x²)=2x²-7x-30-x²-5x-6+12-x-x²=-13x-24

cand ai (a+b)(c+d)=a*c+a*d+b*c+b*d
(a+b)(c-d)=a*c-a*d+b*c-b*d