Question

Phân tích đa thức thành nhân tử 

a^2-b^2-5a+5b

a^2-b^2-3ab^2-3a^2b

x^2-xy+2y-4

4a^2-10ax+15x-9

 

Answer 1

Answer 2

a) Ta có: \(a^2-b^2-5a+5b\)

\(=\left(a-b\right)\left(a+b\right)-5\left(a-b\right)\)

\(=\left(a-b\right)\left(a+b-5\right)\)

b) Ta có: \(a^2-b^2-3ab^2-3a^2b\)

\(=\left(a-b\right)\left(a+b\right)-3ab\left(a+b\right)\)

\(=\left(a+b\right)\left(a-b-3ab\right)\)

Answer 3

c) Ta có: \(x^2-xy+2y-4\)

\(=\left(x^2-4\right)-\left(xy-2y\right)\)

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

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

d) Ta có: \(4a^2-10ax+15x-9\)

\(=\left(4a^2-9\right)-\left(10ax-15x\right)\)

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

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