当x取何整数值时,能使下式值为正整数.
问题描述:
当x取何整数值时,能使下式值为正整数.
(x^4+x^2-2)/(x^3-x^2+x-1)×(x-1)/(x^3+2x^2+2x+4)×(-2)/(x^3-x-x^2+1)
答
(x^4+x^2-2)/(x^3-x^2+x-1)×(x-1)/(x^3+2x^2+2x+4)×(-2)/(x^3-x-x^2+1)=(x^2+2)(x^2-1)/[(x-1)(x^2+1)] * (x-1)/[(x+2)(x^2+2)] * (-2)/[(x-1)(x^2-1)]= -2/[(x-1)(x^2+1)]那么当(x-1)(x^2+1)=正负1或正负2时,表...