答案应为 1/841首先原式化为(4x1四次方+1)(4x3四次方+1)..(4x19四次方+1)/(4x2四次方+1)(4x4四次方+1)...(4x20四次方+1)按照a^2+b^2=(a+b)^2-2ab分解因式4x(2n-1)^4+1=[2x(2n-1)^2+1]^2-4x(2n-1)^2=[2x(2n-1)^2+1+2x...