1.若a^3=-27·x^9·y^3·z^6,则a=(?)

问题描述:

1.若a^3=-27·x^9·y^3·z^6,则a=(?)
2.已知a=5,b=-(1/5),求a^2n+2 · b^2n · b^4
3.(b^m+1)^4 ·(b^m-1)^3=

1)a^3=-27x^9y^3z^6=(-3x^3yz^2)^3,a=-3x^3yz^22)a^(2n+2)b^2nb^4=a^(2n+2)b^(2n+2)b^2=(ab)^(2n+2)b^2=(-1)^(2n+2)b^2=1/253)[b^(m+1)]^4[b^(m-1)]^3=b^(4m+4)b^(3m-3)=b^(7m+1)