数学归纳法证明x^(2n
(1) n=1时 原式=x+y 显然能被x+y整除
(2) 设n=k时结论成立 则x^(2k-1)+y^(2k-1)能被x=y整除
(3) 当n=k+1时
原式=x^[2(k+1)-1]+y^[2(k+1)-1]
=x^(2k+1)+y(2k+1)
=x^(2k-1)*x^2+y^(2k-1)*y^2
=x^(2k-1)*x^2-x^(2k-1)*y^2+x^(2k-1)*y^2+y^(2k-1)*y^2
=[x^(2k-1)*x^2-x^(2k-1)*y^2]+[x^(2k-1)*y^2+y^(2k-1)*y^2]
=[x^(2k-1)*(x^2-y^2)]+{[x^(2k-1)+y^(...全部
(1) n=1时 原式=x+y 显然能被x+y整除
(2) 设n=k时结论成立 则x^(2k-1)+y^(2k-1)能被x=y整除
(3) 当n=k+1时
原式=x^[2(k+1)-1]+y^[2(k+1)-1]
=x^(2k+1)+y(2k+1)
=x^(2k-1)*x^2+y^(2k-1)*y^2
=x^(2k-1)*x^2-x^(2k-1)*y^2+x^(2k-1)*y^2+y^(2k-1)*y^2
=[x^(2k-1)*x^2-x^(2k-1)*y^2]+[x^(2k-1)*y^2+y^(2k-1)*y^2]
=[x^(2k-1)*(x^2-y^2)]+{[x^(2k-1)+y^(2k-1)]*y^2}
=[x^(2k-1)*(x+y)*(x-y)]+{[x^(2k-1)+y^(2k-1)]*y^2}
x^(2k-1)*(x+y)*(x-y)显然能被x+y整除
由(2)知[x^(2k-1)+y^(2k-1)]*y^2能被x+y整除
所以它们的和一定能被x+y整除
所以n=k+1时成立
证毕
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