偶函数.
f(x)=[(1/2)+1/(2^x-1)]x^3.
f(-x)
=[(1/2)+1/(2^(-x)-1)](-x)^3
=-[(2^x+1)/(2-2*2^x)]*x^3
=[(1/2)+1/(2^x-1)]x^3.
=f(x)
故为偶函数.
偶函数.
f(x)=[(1/2)+1/(2^x-1)]x^3.
f(-x)
=[(1/2)+1/(2^(-x)-1)](-x)^3
=-[(2^x+1)/(2-2*2^x)]*x^3
=[(1/2)+1/(2^x-1)]x^3.
=f(x)
故为偶函数.