怎么证明(x2-1)lnx大于等于(x-1)2(x大于0)

问题描述:

怎么证明(x2-1)lnx大于等于(x-1)2(x大于0)

当X=1或-1时,成立当X属于(0,1)时,(x2-1)lnx大于等于(x-1)2就等价于lnx小于等于(x-1)2/(x2-1)即lnx小于等于(x-1)/(x+1)令fu(x)=lnx-(x-1)/(x+1)【此时要证明f(x)小于等于0】其导数大于0,f(x)单调递增,而当x=e时f(x)...