(-a)^5·(-a)^3·a^228a^4b^2÷7a^3b(-x-2y)(-x+2y)(-1/2x-1/5y)^2若x^(3n)=3,则x(6n)=若16^2×8^3=2^n,则n=(1.25×10^8)×(-8×10^5)×(-3×10^3)=(-1/2x^2y^3)×(1/5x^2-2xy+1/3)=

Question

(-a)^5·(-a)^3·a^2
28a^4b^2÷7a^3b
(-x-2y)(-x+2y)
(-1/2x-1/5y)^2
若x^(3n)=3,则x(6n)=
若16^2×8^3=2^n,则n=
(1.25×10^8)×(-8×10^5)×(-3×10^3)=
(-1/2x^2y^3)×(1/5x^2-2xy+1/3)=

Answer 1

(-a)^5·(-a)^3·a^2=（-a)^(5+3+2)=(-a)^10=a^10
28a^4b^2÷7a^3b=4ab
(-x-2y)(-x+2y)=(-x)^2-(2y)^2=x^2-4y^2
(-1/2x-1/5y)^2=[(-5y-2x）/10xy]^2=(25y^2+20xy+4y^2)/100x^2y^2
若x^(3n)=3,则x(6n)=[x^(3n)]^2=9
若16^2×8^3=2^n,则n=17
(1.25×10^8)×(-8×10^5)×(-3×10^3)=1.25*8*3*10^(8+5+3)=30*10^16
(-1/2x^2y^3)×(1/5x^2-2xy+1/3)=-1/10x^4y^3+x^3y^4-1/6x^2y^3