a)原式=2ab^2
b)原式=(a^(-2))/(0.25*b^(-4))=4a^(-2)b^4
c)原式=(6x^(-1))/(4x^2)=(3/2)*x^(-3)
e)原式=(81x^8*y^4)/(625y^12)*(5y)/(3x^2)*y^4=(27/125)*x^6*y^(-3)
f)原式=(x^9*y^6)^(1/3)=x^3*y^2
2ab^2 4b^4/(a^2) 18(a^6)(b^10) 3/(2x^3) 27y^9/(125x^6) 最后也看不清如果是开3次方的话是(x^3)(y^2)
(1)27x^10*y^21/125
(2)x^3*y^2