Question

计算limx→1 sin(x-1)/x²-1=?

Answer 1

当x→1时,
limsin(x-1)/(x²-1)
=limsin(x-1)/(x-1) *1/(x+1)
=limsin(x-1)/(x-1)*lim1/(x+1)
=1*1/(1+1)
=1/2.