∵x^(2n)=2∴xⁿ=√2或xⁿ=-√2 x^(3n)=±2√2 [2x^(3n)]²-(3x^n)²=[2*（±2√2）]²-[3*(±√2)]²=32-18=14 法2[2x^(3n)]²-(3x^n)²=4*x^(6n)-9*x^(2n)=4*[x^(2n)]³-...