Question

phân tích đa thức thành nhân tử

A = \(b^4-9a^2-4b^2+4\)

Answer 1

\(A=b^4-9a^2-4b^2+4=b^4-4b^2+4-9a^2\)

\(=\left(b^2-2\right)^2-9a^2\)

\(=\left(b^2-2+3a\right)\left(b^2-2-3a\right)\)

Answer 2

\(A=b^4-9a^2-4b^2+4\)

\(A=\left(b^2\right)^2-2.2.b^2+2^2-9a^2\)

\(A=\left(b^2-2\right)^2-\left(3a\right)^2\)

\(A=\left(b^2-2-3a\right)\left(b^2-2+3a\right)\)

_Hắc phong_

Answer 3

\(Â=b^4-9a^2-4b^2+4\)

     \(=b^4-4b^2+4-\left(3a\right)^2\)

     \(=\left(b^2-2\right)^2-\left(3a\right)^2=\left(b-2+3a\right)\left(b-2-3a\right)\)