Question

Phân tích đa thức thành nhân tử 

a) 4x^2 +4x-3x

b) x^2+7x+10

c) x^2-x-12

d) x^2+3x-18

 

Answer 1

a) 4x² + 4x - 3x = 4x² +x = x( 4x+1)

b) x²+7x+10= x²+2x+5x+10= x(x+2)+5(x+2)= (x+5)(x+2)

c) x²-x-12= x² - 4x+3x-12= x(x-4)+3(x-4)=(x+3)(x-4)

d) x²+3x-18=x²+6x-3x-18= x(x+6)-3(x+6)=(x-3)(x+6)

Answer 2

\(x^2+7x+10\)

\(=x^2+2x+5x+10\)

\(=x\left(x+2\right)+5\left(x+2\right)\)

\(=\left(x+2\right)\left(x+5\right)\)