求极限lim(x→5)根号(x-1)-2/x-5
问题描述:
求极限lim(x→5)根号(x-1)-2/x-5
答
=ln[ exp( x^2-6x+4 / x-5) ]
=ln[ exp( x^2-6x+4)-exp(x-5) ]
lim x - 5
=ln[ exp(-1)-1 ]
=ln( 1/e -1 )