Q.

Let m and n be number of points at which the function f(x)=max {x,x3,x5,...,x21}, xR, is not differentiable and not continuous, respectively, Then m + n is equal to __________.           [2025]


Ans.

(3)

Here, f(x)={x,x<1x21,1x<0x,0x<1x21,x1 is continuous everywhere.

Then, n = 0

 f'(x)={1,x<121x20,1x<01,0x<121x20,x1 is not differentiable at

x=1,0,1  m=3

So, m + n = 3.