解：(1-1/2)(1+1/2)(1-1/3)(1+1/3)…(1-1/10)(1+1/10) =1/2×3/2×2/3×4/3...10/9×9/10×11/10 =1/2×11/10 =11/20
解：(1-1/2)(1+1/2)(1-1/3)(1+1/3)…(1-1/10)(1+1/10) =(1/2)(3/2)(2/3)(4/3)(3/4)(5/4)…(9/10)(11/10) =(1/2)[(3/2)(2/3)][(4/3)(3/4)]…[(10/9)(9/10)](11/10) =11/20
答：结果是5/6。详情>>
答：x^4+4=x^4+4x^2+4-4x^2=(x^2+2x+2)(x^2-2x+2) =(x+1+i)(x+1-i)(x-1+i)(x-1-i)详情>>
