Given thatf(x)=∣x2−2x−3∣e(9x2−12x+4)
Differentiating on both sides
f′(x)=∣x2−2x−3∣.e(9x2−12x+4).(18x−12)+x2−2x−3∣x2−2x−3∣.(2x−2).e(9x2−12x+4)
⇒f′(x)=∣x2−2x−3∣.e(9x2−12x+4)(18x−12)+x2−2x−3(2x−2)
⇒f′(x)=∣x2−2x−3∣.e(9x2−12x+4).x2−2x−318x3−36x2−54x−12x2+24x+36+2x−2
⇒f′(x)=∣x2−2x−3∣.e(9x2−12x+4).(x−3)(x+1)18x3−48x2−28x+34
Here f′(x) is not defined at x=-1&x=3.
f(x)is not differentiable at two points.