已知:多项式x²-(3k-1)xy-3k²+3mxy-8中不含xy项,求8^k×4÷2^3m+2

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已知:多项式x²-(3k-1)xy-3k²+3mxy-8中不含xy项,求8^k×4÷2^3m+2

-(3k-1)+3m=0
3m-3k+1=0
3m-3k=-1
8k+1次方×4÷2的3m+2次方
=8^(k+1)×4÷2^(3m+2)
=2^3(k+1)×2^2÷2^(3m+2)
=2^[3(k+1)+2-(3m+2)]
=2^[3k+3+2-3m-2]
=2^[3k-3m+3]
=2^[-1+3]
=2^2
=4

∵多项式x²-(3k-1)xy-3k²+3mxy-8中不含xy项
∴合并后 xy系数为0
∴-(3k-1)+3m=0
化简后k-m=-1/3
8^k×4÷2^3m+2=(2^3k)×(2^2)÷(2^3m)=2^(3k+2-3m)=2^[3(k-m)+2]=2^(3×1/3+2)=8
【不知看没看得懂啊?】