Prove that the function remains discontinuous at x = 0, regardless of the choice of k.
To prove given f(x) is discontinuous at x = 0, we have to show that left–hand limit(LHL) and right–hand limit(RHL) is unequal.
LHL = , since (c–h)<c
RHL = = , since (c + h)>c
LHL
–1
RHL
1
since
The function f(x)remains discontinuous at x = 0, regardless the choice of k.