Bài 1:
a: \(M=2x^3y\left(2x^2-3y+5yz\right)\)
\(=4x^5y-6x^3y^2+10x^3y^2z\)
b: \(N=\left(-\dfrac{1}{3}xy^3\right)\cdot\left(-3x^3+6xy-3x\right)\)
\(=x^4y^3-2x^2y^4+x^2y^3\)
c: \(P=\dfrac{-1}{3}a^2b^2\left(6a+\dfrac{2}{3}a^2-b\right)\)
\(=-2a^3b^2+\dfrac{-2}{9}a^4b^2+\dfrac{1}{3}a^2b^3\)