\(x^8+3x^4+1=\left(x^8+\frac{2.3x^4}{2}+\frac{9}{4}\right)-\frac{5}{4}\)
\(=\left(x^4+\frac{3}{2}\right)^2-\frac{5}{4}=\left(x^4+\frac{3-\sqrt{5}}{2}\right)\left(x^4+\frac{3+\sqrt{5}}{2}\right)\)
Kết quá của t là: \(\left(x^4-\frac{-3+\sqrt{5}}{2}\right)\left(x^4+\frac{3+\sqrt{5}}{2}\right)\)
Ghê chưa