17．已知函数f(x)={∣x+1∣,x⩽0∣log2x∣,x>0f(x)=\left\{{\left.\begin{array}{l}{\vert {x+1}\vert ,x\leqslant 0}\\ {\vert {{{\log }_2}x}\vert ,x>0}\end{array}\right.}\right.f(x)={∣x+1∣,x⩽0∣log2x∣,x>0，若方程f(x)=a(a∈R)f(x)=a(a\in R)f(x)=a(a∈R)有四个不同的解x1x_{1}x1，x2x_{2}x2，x3x_{3}x3，x4x_{4}x4，且x1<x2<x3<x4x_{1}<x_{2}<x_{3}<x_{4}x1<x2<x3<x4，则(x1+x2)x4(x_{1}+x_{2})x_{4}(x1+x2)x4的取值范围是((( )))