F(x)=[2f(x)]/[g(x)-1]+f(x)
F(-x)=[2f(-x)]/[g(-x)-1]+f(-x)
=[-2f(x)]/[1/g(x)-1]-f(x)
=g(x)[-2f(x)]/[1-g(x)]-f(x)
=g(x)[2f(x)]/[g(x)-1]-f(x)
不奇不偶.
F(x)=[2f(x)]/[g(x)-1]+f(x)
F(-x)=[2f(-x)]/[g(-x)-1]+f(-x)
=[-2f(x)]/[1/g(x)-1]-f(x)
=g(x)[-2f(x)]/[1-g(x)]-f(x)
=g(x)[2f(x)]/[g(x)-1]-f(x)
不奇不偶.