Question

求下列函数图形的拐点及凹凸区间,

Answer 1

y'=1-(x^2+1)/(x^2-1)^2=0

x=+-根号3或x=0

y''=2x(x^2-1)(x^2+3)/(x^2-1)^4=0

x=0或x=+-1

而x=+-1是间断点

所以拐点是x=0

x