Bài 1: Thu gọn đơn thức ( a là hằng só )
a) \(1\dfrac{1}{4}x^2y\left(\dfrac{-5}{6}xy\right)^0.\left(-2\dfrac{1}{3}xy\right)\)
b) \(\dfrac{1}{2}x.\dfrac{1}{4}x^2.\dfrac{x^3}{8}.2y.4y^2.x^3\)
c) \(\left(\dfrac{-9}{2}\right)^3.3xy\left(4a^2x^3\right)\left(4\dfrac{1}{3}ay^2\right)\)
d) \(\left(\dfrac{1}{3}xy^2\right)^3\left(\dfrac{-3}{7}x^4y\right)^2\)