Question

phân tích đa thức thành nhân tử 

\(8x^3+60x^2y+150xy^2+125y^3\)

Answer 1

\(8x^3+60x^2y+150xy^2+125y^3\)

\(=\left(8x^3+125y^3\right)+\left(60x^2y+150xy^2\right)\)

\(=\left(2x+5y\right)\left(4x^2-10xy+25y^2\right)+30xy\left(2x+5y\right)\)

\(=\left(2x+5y\right)\left(4x^2-10xy+25y^2+30xy\right)\)

\(=\left(2x+5y\right)\left(4x^2+20xy+25y^2\right)\)

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

Answer 2

C2 : Áp dụng luôn HĐT ( x + y ) ³

\(8x^3+60x^2y+150xy^2+125y^3\)

\(=\left(2x\right)^3+3.\left(2x\right)^2.5y+3.2x.\left(5y\right)^2+\left(5y\right)^3\)

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

=.= hok tốt!!