\(x^2y^4+2xy^2+1=\left(xy^2\right)^2+2.xy^2.1+1^2=\left(xy^2+1\right)^2\)
Áp dụng hằng đẳng thức thứ nhất: \(\left(a+b\right)^2=a^2+2ab+b^2\)
\(2xy^2+x^2y^4+1\)
\(=\left(xy^2\right)^2+2xy^2+1\)
\(=\left(xy^2+1\right)^2\)
\(2xy^2+x^2y^4+1\)
\(=\left(xy^2\right)^2+2xy^2.1+1^2\)
\(=\left(xy^2+1\right)^2\)
\(2xy^2+x^2y^4+1\)
\(=\left(x^2y^4+xy^2\right)+\left(xy^2+1\right)\)
\(=xy^2\left(xy^2+1\right)+\left(xy^2+1\right)\)
\(=\left(xy^2+1\right)\left(xy^2+1\right)\)
\(\Rightarrow\left(xy^2+1\right)^2\)
\(2xy^2+x^2y^4+1\)
\(=\left(xy^2\right)^2+2xy^2+1\)
\(=\left(xy^2+1\right)^2\)
