高数第二题计算题?

2025-03-02 00:09:57
推荐回答(1个)
回答1:

(2)
lim(x->1+) [√(x-1)+√x -1]/√(x^2-1) (0/0分子分母分别求导)
=lim(x->1+) { 1/[2√(x-1)]+1/(2√x) }/ [x/√(x^2-1)]
=lim(x->1+) √(x^2-1) .{ 1/[2√(x-1)]+1/(2√x) } / x
=lim(x->1+) .{ √(x+1)/2+ √(x^2-1)/(2√x) } / x
=( √2/2 + 0) /1
=√2/2