Find which of the functions is continuous or discontinuous at the indicated points:


at x = 2

Given,


…(1)


We need to check its continuity at x = 2


A function f(x) is said to be continuous at x = c if,


Left hand limit(LHL at x = c) = Right hand limit(RHL at x = c) = f(c).


Mathematically we can represent it as-



Where h is a very small number very close to 0 (h0)


Now according to above theory-


f(x) is continuous at x = 2 if -



Clearly,


LHL = {using equation 1}


LHL =


LHL =


LHL =


LHL = 5 -2(0) = 5 …(2)


Similarly we proceed for RHL-


RHL = {using equation 1}


RHL =


RHL =


RHL =


RHL = 5 + 2(0) = 5 …(3)


And,


f(2) = 5 {using eqn 1} …(4)


Clearly from equation 2 , 3 and 4 we can say that



f(x) is continuous at x = 2


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