Question

pt đa thức thành nhân tử A=2(x+y)^4-3(x+y)^2-5

Answer 1

Answer 2

Ta có: \(A=2\left(x+y\right)^4-3\left(x+y\right)^2-5\)

\(=2\left(x+y\right)^4-5\left(x+y\right)^2+2\left(x+y\right)^2-5\)

\(=\left(x+y\right)^2\left[2\left(x+y\right)^2-5\right]+\left[2\left(x+y\right)^2-5\right]\)

\(=\left[2\left(x+y\right)^2-5\right]\left[\left(x+y\right)^2+1\right]\)