a) \(4x^2-4y^2=4\left(x^2-y^2\right)=4\left(x+y\right)\left(x-y\right)\)
b) \(=x\left(x+y\right)-2\left(x+y\right)=\left(x+y\right)\left(x-2\right)\)
c) \(6x^2-7x+2=6x^2-4x-3x+2=\left(2x-1\right)\left(3x-2\right)\)
Bài 2 : Bị mờ
Bài 3 : Mờ
Bài 3:
a: Thay x=5 vào B, ta được:
B=(5-1)/(5+3)=2/8=1/4
b: \(A=\dfrac{2x^2+6x+x^2-3x-2x^2-3x-1}{\left(x-3\right)\left(x+3\right)}=\dfrac{-1}{\left(x-3\right)\left(x+3\right)}\)