Q.

Let f:(-2,2)→R be defined by f(x)={x[x],-2<x<0(x-1)[x],0≤x<2 where [x] denotes the greatest integer function. If m and n respectively are the number of points in (- 2, 2) at which y=|f(x)| is not continuous and not differentiable, then m+n is equal to _____.            [2023]


Ans.

(4)

f(x) or |f(x)|={-2x,-2<x<-1-x,-1≤x<00,0≤x≤1x-1,1≤x<2

Point of discontinuity: m=-1 i.e., one in number Point of non-differentiability: n=-1,0,1 i.e., 3 in number.



∴  m+n=1+3=4