Question

phân tích thành nhân tử 
a, 2x(x-3y)+5x-15y 
b,x^2-y^2-2x+1

Answer 1

a: =2x(x-3y)+5(x-3y)

=(x-3y)(2x+5)

b: =(x-1)^2-y^2

=(x-1-y)(x-1+y)

Answer 2

\(a,2x\left(x-3y\right)+5x-15y=2x\left(x-3y\right)+5\left(x-3y\right)=\left(x-3y\right)\left(2x+5\right)\)

\(b,x^2-y^2-2x+1=\left(x^2-2x+1\right)-y^2=\left(x-1\right)^2-y^2=\left(x-1-y\right)\left(x-1+y\right)\)

Answer 3

a)

\(2x\left(x-3y\right)+5x-15y\\ =2x\left(x-3y\right)+5\left(x-3y\right)\\ =\left(x-3y\right)\left(2x+5\right)\)

b)

\(x^2-y^2-2x+1\\ =\left(x^2-2x+1\right)-y^2\\ =\left(x-1\right)^2-y^2\\ =\left(x-1-y\right)\left(x-1+y\right)\)