Question

rút gọn \(\left(-\dfrac{2007}{3}xy\right)^8\left(-\dfrac{6}{2007}x^2y\right)^8\)

Answer 1

Lời giải:

Gọi đa thức là $T$

\(T=(\frac{-2007}{3})^8(xy)^8.(\frac{-6}{2007})^8(x^2y)^8\)

\(=\frac{2007^8}{3^8}.x^8y^8.\frac{6^8}{2007^8}.x^{16}.y^8\)

\(=\frac{6^8}{3^8}.x^{8+16}.y^{8+8}=2^8.x^{24}y^{16}\)

Answer 2

Ta có: \(\left(-\dfrac{2007}{3}xy\right)^8\cdot\left(-\dfrac{6}{2007}x^2y\right)^8\)

\(=\left(\dfrac{2007}{3}\cdot\dfrac{6}{2007}\right)^8\cdot x^8\cdot x^{16}\cdot y^8\cdot y^8\)

\(=256x^{24}y^{16}\)