Continuity and DifferentiabilityHard
Question
The function f(x) = [x] cos
[.] denotes the greatest integer function, is discontinu ous at
[.] denotes the greatest integer function, is discontinu ous atOptions
A.all x
B.all integer points
C.no x
D.x which is not an integer
Solution
Here, f(x) = [x]cos 
∴ f(x)
which shows RHL = LHL at x = n∈ Integer as if x = 1
⇒
cos
π = 0
and
0 = 0
Also, f(x) = 0
Similarly, when x = 2
⇒
f(x) =
f(x) = 0
Thus function is discontinuous at no x.
Hence,(c) is the correct ancwer.

∴ f(x)
which shows RHL = LHL at x = n∈ Integer as if x = 1
⇒
cos
π = 0and
0 = 0Also, f(x) = 0
Similarly, when x = 2
⇒
f(x) =
f(x) = 0Thus function is discontinuous at no x.
Hence,(c) is the correct ancwer.
Create a free account to view solution
View Solution FreeMore Continuity and Differentiability Questions
If y = , then is equal to -...If y = sin(m sin-1 x), then (1 - x2) y″ - xy′ is equal to...The functions u = ex sin x; v = ex cos x satisfy the equation...If f is a real-valued differentiable function satisfying | f(x) - f(y) | ≤ (x - y)2, x, y ∈ R and f(0) = 0, ...If y = sin (m sin-1x), then (1 - x2) y″ -xy′ is equal to -...