Question

efetue as mulltiplicaçoes : 
3y(4x2-2x3-7)=

(x4-3x2-5x+1)(-4x)= 

2x(y2+xy+1)=

4ab(a2+b2-ab)=  
,
(2x+3)(5x-1)=  

(2x-3)(x-1) =

(x2-2x)(x3-3x2)=

Answer 1

a) $3y(4x^2-2x^3-7)=12x^2y-6x^3y-21y$

b) $(x^4-3x^2-5x+1)(-4x)=-4x^5+12x^3+20x^2-4x$

c) $2x(y^2+xy+1)=2xy^2+2x^2y+2x$

d) $4ab(a^2+b^2-ab)=4a^3b+4ab^3-4a^2b^2$

e) $(2x+3)(5x-1)=10x^2-2x+15x-3=10x^2+13x-3$

f) $(2x-3)(x-1)=2x^2-2x-3x+3=2x^2-5x+3$

g) $(x^2-2x)(x^3-3x^2)=x^5-3x^4-2x^4+6x^3=x^5-5x^4+6x^3$

Answer 2

3y(4x2-2x3-7)=  12x2y  - 6x3y - 21y

(x4-3x2-5x+1)(-4x)= - 4x5 + 12x3 - 20x2 - 4x

2x(y2+xy+1)= 2xy2 + x2y + 2x

4ab(a2+b2-ab)= 4a3b + 4ab3 - 4a2b2
,
(2x+3)(5x-1)= 10x2 - 2x +15x - 3 ==> 10x2 + 13x - 3

(2x-3)(x-1) = 2x2 - 2x - 3x + 3 ==> 2x2 - 5x + 3

(x2-2x)(x3-3x2)= x5 - 3x4 - 2x4 + 6x3 ==> x5 - 5x4 + 6x3