若x^2n=7 则(x^3n)^2 =_____

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若x^2n=7则(x^3n)^2=_____若x^2n=7则(x^3n)^2=_____若x^2n=7则(x^3n)^2=_____答:若x^2n=7则(x^3n)^2=_343解(x^3n)^2=x

若x^2n=7 则(x^3n)^2 =_____
若x^2n=7 则(x^3n)^2 =_____

若x^2n=7 则(x^3n)^2 =_____
答:若x^2n=7 则(x^3n)^2 =_343
解 (x^3n)^2=x^(6n)=(x^2n)^3=7^3=343

343
可以追问

(x^3n)^2 =(x^2n)^3= 343

147

(x^3n)^2 =(x^2n)~3=7~3=343

x^2n=x^n×x^n=7
即x^n=√7
(x^3n)^2=(x^n×x^n×x^n)(x^n×x^n×x^n)
=√7×√7×√7×√7×√7×√7=343