Find the points of discontinuity, if any, of the following functions: (i) f(x)=\left\{\begin{array}{c}x^{3}-x^{2}+2 x-2, \text { if } x \neq 1 \\ 4, \text { if } x=1\end{array}\right. (ii) f(x)=\left\{\begin{array}{l}\frac{x^{4}-16}{x-2}, \text { if } x \neq 2 \\ 16, \text { if } x=2\end{array}\right.
Find the points of discontinuity, if any, of the following functions: (i) f(x)=\left\{\begin{array}{c}x^{3}-x^{2}+2 x-2, \text { if } x \neq 1 \\ 4, \text { if } x=1\end{array}\right. (ii) f(x)=\left\{\begin{array}{l}\frac{x^{4}-16}{x-2}, \text { if } x \neq 2 \\ 16, \text { if } x=2\end{array}\right.

(i)

A real function f is said to be continuous at x = c, where c is any point in the domain of f if

RD Sharma Solutions for Class 12 Maths Chapter 9 Continuity Image 102

h is a very small positive number. i.e. left hand limit as x → c (LHL) = right hand limit as x → c (RHL) = value of function at x = c.

A function is continuous at x = c if

RD Sharma Solutions for Class 12 Maths Chapter 9 Continuity Image 103

Function is defined for all real numbers so we need to comment about its continuity for all numbers in its domain (domain = set of numbers for which f is defined)

Function is changing its nature (or expression) at x = 1, so we need to check its continuity at x = 1.

=>   f (1) = 4 [using equation 1]

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∴ f (x) is discontinuous at x = 1.

Let c be any real number such that c ≠ 0

RD Sharma Solutions for Class 12 Maths Chapter 9 Continuity Image 105

(ii)

A real function f is said to be continuous at x = c, where c is any point in the domain of f if

RD Sharma Solutions for Class 12 Maths Chapter 9 Continuity Image 107

h is a very small positive number. i.e. left hand limit as x → c (LHL) = right hand limit as x → c (RHL) = value of function at x = c.

A function is continuous at x = c if

RD Sharma Solutions for Class 12 Maths Chapter 9 Continuity Image 108

The function is defined for all real numbers, so we need to comment about its continuity for all numbers in its domain (domain = set of numbers for which f is defined)

Function is changing its nature (or expression) at x = 2, so we need to check its continuity at x = 2 first.

=> f (2) = 16 [from equation 1]

RD Sharma Solutions for Class 12 Maths Chapter 9 Continuity Image 109

∴ f (x) is continuous at x = 2.

Let c be any real number such that c ≠ 0

RD Sharma Solutions for Class 12 Maths Chapter 9 Continuity Image 110