Show that the functionis discontinous at x=0. from Mathematics

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsLong Answer Type

31. Discuss continuity of f(x) at x = 0, if
straight f left parenthesis straight x right parenthesis equals open curly brackets table attributes columnalign left end attributes row cell fraction numerator square root of 1 plus straight x minus end root square root of 1 minus straight x end root over denominator sin space straight x end fraction comma space if space space straight x not equal to 0 end cell row cell space space space space space space space space space space space space 1 space space space space space space space space space space space space space space space space space space comma space if space straight x equals 0 end cell end table close
125 Views

 Multiple Choice QuestionsShort Answer Type

32.

Determine if f is defined by
 straight f left parenthesis straight x right parenthesis equals open curly brackets table attributes columnalign left end attributes row cell straight x squared space sin 1 over straight x comma space straight x not equal to 0 end cell row cell space space 0 space space space space space comma space straight x equals 0 end cell end table close

74 Views

33.

Determine if f define by
straight f left parenthesis straight x right parenthesis equals open curly brackets table attributes columnalign left end attributes row cell fraction numerator sin space straight x over denominator straight x end fraction plus space cos space straight x comma space straight x not equal to 0 end cell row cell space space space space space space space space space space 2 space space space space space comma space straight x equals 0 end cell end table close
at space straight x equals 0

95 Views

 Multiple Choice QuestionsLong Answer Type

34.

Determine if f is definend by
straight f left parenthesis straight x 0 right parenthesis equals open curly brackets table attributes columnalign left end attributes row cell xsin 1 over straight x comma space straight x not equal to 0 end cell row cell space space 0 space space space space comma space straight x equals 0 end cell end table close

76 Views

Advertisement

 Multiple Choice QuestionsShort Answer Type

35. Find all points of continuity of f, where
straight f left parenthesis straight x right parenthesis equals open curly brackets table attributes columnalign left end attributes row cell fraction numerator sin space straight x over denominator straight x end fraction comma space straight x less than 0 end cell row cell space straight x plus 1 space comma space straight x greater or equal than 0 end cell end table close
at space straight x equals 0


79 Views

36. Discuss the continuity of the function

straight f left parenthesis straight x right parenthesis equals open curly brackets table attributes columnalign left end attributes row cell fraction numerator 1 minus cos 4 straight x over denominator straight x squared end fraction comma space straight x not equal to 0 end cell row cell space space space space space space space 8 space space space space comma space straight x equals 0 end cell end table close
at space straight x equals 0
83 Views

 Multiple Choice QuestionsLong Answer Type

37. If space straight f left parenthesis straight x right parenthesis equals open curly brackets table attributes columnalign left end attributes row cell open vertical bar straight x close vertical bar sin 1 over straight x comma space if space straight x not equal to 0 end cell row cell space space space space space space space 0 comma space space space space space if space straight x equals 0 end cell end table close
then discuss continuity of f(x) at x = 0.
74 Views

 Multiple Choice QuestionsShort Answer Type

38. Discuss the continuity at x = 0 of the function

straight f left parenthesis straight x right parenthesis equals open curly brackets table attributes columnalign left end attributes row cell open vertical bar straight x close vertical bar space cos 1 over straight x comma space straight x equals 0 end cell row cell space space space space space space 0 space space space space comma space straight x equals 0 end cell end table close
104 Views

Advertisement
Advertisement

39. Show that the function
straight f left parenthesis straight x right parenthesis equals open curly brackets table attributes columnalign left end attributes row cell fraction numerator straight e to the power of 1 over straight x end exponent minus 1 over denominator straight e to the power of begin display style 1 over straight x plus 1 end style end exponent end fraction comma space straight x not equal to 0 end cell row cell space space space space space space 0 space space space space space space space comma space straight x equals 0 end cell end table close
is discontinous at x=0.


Here space straight f left parenthesis straight x right parenthesis equals open curly brackets table attributes columnalign left end attributes row cell fraction numerator straight e to the power of 1 over straight x end exponent minus 1 over denominator straight e to the power of begin display style 1 over straight x plus 1 end style end exponent end fraction comma space straight x not equal to 0 end cell row cell space space space space space space 0 space space space space space space space comma space straight x equals 0 end cell end table close
Lt with straight x rightwards arrow 0 to the power of minus below straight f left parenthesis straight x right parenthesis equals Lt with straight x rightwards arrow 0 to the power of minus below fraction numerator straight e to the power of 1 over straight x end exponent minus 1 over denominator straight e to the power of 1 over straight x end exponent plus 1 end fraction space space space space space space space space space space left square bracket Put space straight x equals 0 minus straight h comma space straight h greater than 0 space so space that space straight h rightwards arrow 0 space as space straight x rightwards arrow 0 to the power of minus right square bracket
space space space space space space space space space space space space space space space equals Lt with straight h rightwards arrow 0 below fraction numerator straight e to the power of begin display style 1 over straight h end style end exponent minus 1 over denominator straight e to the power of 1 over straight h end exponent plus 1 end fraction equals fraction numerator 0 minus 1 over denominator 0 plus 1 end fraction space space space space space space space space space space space space space space space space space space space open square brackets because straight e to the power of negative 1 over straight h rightwards arrow 0 space as space straight h rightwards arrow 0 end exponent close square brackets
space space space space space space space space space space space space space space space equals negative 1

Lt with straight x rightwards arrow 0 to the power of plus below straight f left parenthesis straight x right parenthesis equals Lt with straight x rightwards arrow 0 to the power of plus below fraction numerator straight e to the power of begin display style 1 over straight x end style end exponent minus 1 over denominator straight e to the power of 1 over straight x end exponent plus 1 end fraction space space space space space space space space space space left square bracket Put space straight x equals 0 plus straight h comma space straight h greater than 0 space so space that space straight h rightwards arrow 0 space as space straight x rightwards arrow 0 to the power of plus right square bracket
space space space space space space space space space space space space space space space equals Lt with straight h rightwards arrow 0 below fraction numerator straight e to the power of begin display style 1 over straight h end style end exponent minus 1 over denominator straight e to the power of 1 over straight h end exponent plus 1 end fraction equals Lt with straight h rightwards arrow 0 below fraction numerator begin display style straight e to the power of begin display style 1 over straight h end style end exponent over straight e to the power of begin display style 1 over straight h end style end exponent end style minus begin display style 1 over straight e to the power of begin display style 1 over straight h end style end exponent end style over denominator straight e to the power of begin display style 1 over straight h end style end exponent over straight e to the power of begin display style 1 over straight h end style end exponent plus 1 over straight e to the power of begin display style 1 over straight h end style end exponent end fraction equals fraction numerator 1 minus straight e to the power of negative begin display style 1 over straight h end style end exponent over denominator 1 plus straight e to the power of negative 1 over straight h end exponent end fraction
space space space space space space space space space space space space space space space space equals fraction numerator 1 minus 0 over denominator 1 plus 0 end fraction space space space space space space space space space space space space space space space space space space space open square brackets because straight e to the power of negative 1 over straight h end exponent rightwards arrow 0 space as space straight h rightwards arrow 0 close square brackets space space
therefore space Lt with straight x rightwards arrow 0 to the power of minus below straight f left parenthesis straight x right parenthesis not equal to Lt with straight x rightwards arrow 0 to the power of plus below straight f left parenthesis straight x right parenthesis
rightwards double arrow space Lt with straight x rightwards arrow 0 below straight f left parenthesis straight x right parenthesis space does space not space exist
⇒ f(x) is discontinuous at x = 0.
75 Views

Advertisement
40. Let space straight f left parenthesis straight x right parenthesis equals open curly brackets table attributes columnalign left end attributes row cell table row cell 2 straight x end cell end table if space straight x less than 2 end cell row cell table row cell 2 space if space straight x equals 2 end cell row cell straight x squared space if space straight x greater than 2 end cell end table end cell end table close
Show that 2 is a removable discontinuity of f.
83 Views

Advertisement