हिंदी

If F (X) = |3 − X| + (3 + X), Where (X) Denotes the Least Integer Greater than Or Equal to X, Then F (X) is (A) Continuous and Differentiable at X = 3 (B) Continuous but Not Differentiable at X = 3 - Mathematics

Advertisements
Advertisements

प्रश्न

If f (x) = |3 − x| + (3 + x), where (x) denotes the least integer greater than or equal to x, then f (x) is

विकल्प

  • continuous and differentiable at x = 3

  • continuous but not differentiable at x = 3

  • differentiable nut not continuous at x = 3

  • neither differentiable nor continuous at x = 3

MCQ

उत्तर

(d) neither differentiable nor continuous at x = 3 

We have,
\[f\left( x \right) = \left| 3 - x \right| + \left( 3 + x \right), \text { where } \left( x \right) \text{denotes the least integer greater than or equal to} x . \]
`f(x) = {(3-x +3+3,2<x<3),(-3 +x + 3 +4,3<x<4):}`
`⇒ f(x) = {(-x +9,2<x<3),(x+4 , 3<x<4):}`
Here, 
\[\left( \text { LHL at x } = 3 \right) = \lim_{x \to 3^-} f\left( x \right) = \lim_{x \to 3^-} \left( - x + 9 \right) = - 3 + 9 = 6\]
\[\left( \text { RHL at x  }= 3 \right) = \lim_{x \to 3^+} f\left( x \right) = \lim_{x \to 3^-} \left( x + 4 \right) = 3 + 4 = 7\]
\[\text { Since, } \left( \text { LHL at x } = 3 \right) \neq \left( \text { RHL at x  }= 3 \right)\]
\[\text{Hence, given function is not continuous at x} = 3\]
\[\text{Therefore, the function will also not be differentiable at} x = 3\]

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 10: Differentiability - Exercise 10.4 [पृष्ठ १९]

APPEARS IN

आरडी शर्मा Mathematics [English] Class 12
अध्याय 10 Differentiability
Exercise 10.4 | Q 22 | पृष्ठ १९

वीडियो ट्यूटोरियलVIEW ALL [4]

संबंधित प्रश्न

Examine the continuity of the following function :

`{:(,,f(x)= x^2 -x+9,"for",x≤3),(,,=4x+3,"for",x>3):}}"at "x=3`


If f(x)= `{((sin(a+1)x+2sinx)/x,x<0),(2,x=0),((sqrt(1+bx)-1)/x,x>0):}`

is continuous at x = 0, then find the values of a and b.


Discuss the continuity of the following functions at the indicated point(s): 

\[f\left( x \right) = \begin{cases}\frac{\left| x^2 - 1 \right|}{x - 1}, for & x \neq 1 \\ 2 , for & x = 1\end{cases}at x = 1\]

Discuss the continuity of the following functions at the indicated point(s): 

\[f\left( x \right) = \left\{ \begin{array}{l}\frac{2\left| x \right| + x^2}{x}, & x \neq 0 \\ 0 , & x = 0\end{array}at x = 0 \right.\]

Determine the value of the constant k so that the function 

\[f\left( x \right) = \left\{ \begin{array}{l}\frac{x^2 - 3x + 2}{x - 1}, if & x \neq 1 \\ k , if & x = 1\end{array}\text{is continuous at x} = 1 \right.\] 


Find the value of k for which \[f\left( x \right) = \begin{cases}\frac{1 - \cos 4x}{8 x^2}, \text{ when}  & x \neq 0 \\ k ,\text{ when }  & x = 0\end{cases}\] is continuous at x = 0;

 


In each of the following, find the value of the constant k so that the given function is continuous at the indicated point; \[f\left( x \right) = \begin{cases}k( x^2 + 2), \text{if} & x \leq 0 \\ 3x + 1 , \text{if} & x > 0\end{cases}\]


Discuss the continuity of the f(x) at the indicated points:  f(x) = | x − 1 | + | x + 1 | at x = −1, 1.

 

Determine if \[f\left( x \right) = \begin{cases}x^2 \sin\frac{1}{x} , & x \neq 0 \\ 0 , & x = 0\end{cases}\] is a continuous function?

 


Given the function  
\[f\left( x \right) = \frac{1}{x + 2}\] . Find the points of discontinuity of the function f(f(x)).

Define continuity of a function at a point.

 

Write the value of b for which \[f\left( x \right) = \begin{cases}5x - 4 & 0 < x \leq 1 \\ 4 x^2 + 3bx & 1 < x < 2\end{cases}\]  is continuous at x = 1.

 


Let f (x) = | x | + | x − 1|, then


If  \[f\left( x \right) = \begin{cases}\frac{\sin (a + 1) x + \sin x}{x} , & x < 0 \\ c , & x = 0 \\ \frac{\sqrt{x + b x^2} - \sqrt{x}}{bx\sqrt{x}} , & x > 0\end{cases}\]is continuous at x = 0, then 


If \[f\left( x \right) = \begin{cases}mx + 1 , & x \leq \frac{\pi}{2} \\ \sin x + n, & x > \frac{\pi}{2}\end{cases}\] is continuous at \[x = \frac{\pi}{2}\]  , then

 


\[f\left( x \right) = \begin{cases}\frac{\sqrt{1 + px} - \sqrt{1 - px}}{x}, & - 1 \leq x < 0 \\ \frac{2x + 1}{x - 2} , & 0 \leq x \leq 1\end{cases}\]is continuous in the interval [−1, 1], then p is equal to

 


If  \[f\left( x \right) = \begin{cases}a \sin\frac{\pi}{2}\left( x + 1 \right), & x \leq 0 \\ \frac{\tan x - \sin x}{x^3}, & x > 0\end{cases}\] is continuous at x = 0, then a equals


The value of k which makes \[f\left( x \right) = \begin{cases}\sin\frac{1}{x}, & x \neq 0 \\ k , & x = 0\end{cases}\]    continuous at x = 0, is

 


Show that f(x) = |x − 2| is continuous but not differentiable at x = 2. 


Find whether the function is differentiable at x = 1 and x = 2 

\[f\left( x \right) = \begin{cases}x & x \leq 1 \\ \begin{array} 22 - x  \\ - 2 + 3x - x^2\end{array} & \begin{array}11 \leq x \leq 2 \\ x > 2\end{array}\end{cases}\]

Show that the function 

\[f\left( x \right) = \begin{cases}\left| 2x - 3 \right| \left[ x \right], & x \geq 1 \\ \sin \left( \frac{\pi x}{2} \right), & x < 1\end{cases}\] is continuous but not differentiable at x = 1.


If f is defined by f (x) = x2, find f'(2).


Discuss the continuity and differentiability of f (x) = |log |x||.


Give an example of a function which is continuos but not differentiable at at a point.


The set of points where the function f (x) given by f (x) = |x − 3| cos x is differentiable, is


Let \[f\left( x \right) = \begin{cases}1 , & x \leq - 1 \\ \left| x \right|, & - 1 < x < 1 \\ 0 , & x \geq 1\end{cases}\] Then, f is 


If f is continuous at x = 0 then find f(0) where f(x) = `[5^x + 5^-x - 2]/x^2`, x ≠ 0


The total cost C for producing x units is Rs (x2 + 60x + 50) and the price is Rs (180 - x) per unit. For how many units the profit is maximum.


If f(x) = `(e^(2x) - 1)/(ax)` .                for x < 0 , a ≠ 0
         = 1.                             for x = 0
         = `(log(1 + 7x))/(bx)`.        for x > 0 , b ≠ 0
is continuous at x = 0 . then find a and b


Find `dy/dx if y = tan^-1 ((6x)/[ 1 - 5x^2])`


If the function f is continuous at x = 2, then find 'k' where

f(x) = `(x^2 + 5)/(x - 1),` for  1< x ≤ 2 
      = kx + 1 , for x > 2


Discuss the continuity of the function f at x = 0, where
f(x) = `(5^x + 5^-x - 2)/(cos2x - cos6x),` for x ≠ 0
      = `1/8(log 5)^2,`  for x = 0


For continuity, at x = a, each of `lim_(x -> "a"^+) "f"(x)` and `lim_(x -> "a"^-) "f"(x)` is equal to f(a).


A continuous function can have some points where limit does not exist.


Examine the differentiability of f, where f is defined by
f(x) = `{{:(1 + x",",  "if"  x ≤ 2),(5 - x",",  "if"  x > 2):}` at x = 2


If f(x) = `{{:("m"x + 1",",  "if"  x ≤ pi/2),(sin x + "n"",",  "If"  x > pi/2):}`, is continuous at x = `pi/2`, then ______.


Write the number of points where f(x) = |x + 2| + |x - 3| is not differentiable.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×