问一道数学题,已知f(x-1/x)=x^2/(1+x^4),求f(x)
问题描述:
问一道数学题,已知f(x-1/x)=x^2/(1+x^4),求f(x)
答
f(x-1/x)=1/[(1/x^2)+x^2]=1/[(x-1/x)^2+2]
令t=x-1/x
f(t)=1/(t^2+2)
f(x)=1/(x^2+2)
答
答:
f(x-1/x)
=x^2/(1+x^4)
=1/(1/x^2+x^2)
=1/[(x-1/x)^2+2]
所以:
f(x)=1/(x^2+2)