मराठी

F(x) = ,if,if{2x2-3x-2x-2,if x≠25,if x=2 at x = 2 - Mathematics

Advertisements
Advertisements

प्रश्न

f(x) = `{{:((2x^2 - 3x - 2)/(x - 2)",", "if"  x ≠ 2),(5",", "if"  x = 2):}` at x = 2

बेरीज

उत्तर

We have, f(x) = `{{:((2x^2 - 3x - 2)/(x - 2)",", "if"  x ≠ 2),(5",", "if"  x = 2):}` at x = 2.

At x = 2

L.H.L. = `lim_(x -> 2^-) (2x^2 - 3x - 2)/(x - 2)`

= `lim_("h" -> 0) (2(2 - "h")^2 - 3(2 - "h") - 2)/((2 - "h") - 2)`

= `lim_("h" -> 0) (8 + 2"h"^2 - 8"h" - 6 + 3"h" - 2)/(-"h")`

= `lim_("h" -> 0) (2"h"^2 - 5"h")/(-"h")`

= `lim_("h" -> 0) ("h"(2"h" - 5))/(-"h")` = 5

R.H.L. = `lim_(x -> 2^+) (2x^2 - 3x - 2)/(x - 2)`

= `lim_("h" -> 0) (2(2 + "h")^2 - 3(2 + "h") - 2)/((2 + "h") - 2)`

= `lim_("h" -> 0) (8 + 2"h"^2 + 8"h" - 6 - 3"h" - 2)/"h"`

= `lim_("h" -> 0) (2"h"^2 + 5"h")/"h"`

= `lim_("h" -> 0) ("h"(2"h" + 5))/"h"` = 5

Also f(2) = 5  ....(Given)

∴ L.H.L. = R.H.L. = f(2)

So, f(x) is continuous at x = 2.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 5: Continuity And Differentiability - Exercise [पृष्ठ १०७]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
पाठ 5 Continuity And Differentiability
Exercise | Q 4 | पृष्ठ १०७

व्हिडिओ ट्यूटोरियलVIEW ALL [4]

संबंधित प्रश्‍न

Let \[f\left( x \right) = \begin{cases}\frac{1 - \cos x}{x^2}, when & x \neq 0 \\ 1 , when & x = 0\end{cases}\] Show that f(x) is discontinuous at x = 0.

 

 


If \[f\left( x \right) = \begin{cases}\frac{x - 4}{\left| x - 4 \right|} + a, \text{ if }  & x < 4 \\ a + b , \text{ if } & x = 4 \\ \frac{x - 4}{\left| x - 4 \right|} + b, \text{ if } & x > 4\end{cases}\]  is continuous at x = 4, find ab.

 


Let\[f\left( x \right) = \left\{ \begin{array}\frac{1 - \sin^3 x}{3 \cos^2 x} , & \text{ if }  x < \frac{\pi}{2} \\ a , & \text{ if }  x = \frac{\pi}{2} \\ \frac{b(1 - \sin x)}{(\pi - 2x )^2}, & \text{ if }  x > \frac{\pi}{2}\end{array} . \right.\] ]If f(x) is continuous at x = \[\frac{\pi}{2}\] , find a and b.

 

If the functions f(x), defined below is continuous at x = 0, find the value of k. \[f\left( x \right) = \begin{cases}\frac{1 - \cos 2x}{2 x^2}, & x < 0 \\ k , & x = 0 \\ \frac{x}{\left| x \right|} , & x > 0\end{cases}\] 

 


Find the values of a and b so that the function f(x) defined by \[f\left( x \right) = \begin{cases}x + a\sqrt{2}\sin x , & \text{ if }0 \leq x < \pi/4 \\ 2x \cot x + b , & \text{ if } \pi/4 \leq x < \pi/2 \\ a \cos 2x - b \sin x, & \text{ if }  \pi/2 \leq x \leq \pi\end{cases}\]becomes continuous on [0, π].


If \[f\left( x \right) = \begin{cases}\frac{x^2 - 16}{x - 4}, & \text{ if }  x \neq 4 \\ k , & \text{ if }  x = 4\end{cases}\]  is continuous at x = 4, find k.


Let  \[f\left( x \right) = \begin{cases}\frac{x^4 - 5 x^2 + 4}{\left| \left( x - 1 \right) \left( x - 2 \right) \right|}, & x \neq 1, 2 \\ 6 , & x = 1 \\ 12 , & x = 2\end{cases}\]. Then, f (x) is continuous on the set

 


The value of f (0), so that the function 

\[f\left( x \right) = \frac{\sqrt{a^2 - ax + x^2} - \sqrt{a^2 + ax + x^2}}{\sqrt{a + x} - \sqrt{a - x}}\]   becomes continuous for all x, given by

If  \[f\left( x \right) = \frac{1}{1 - x}\] , then the set of points discontinuity of the function f (f(f(x))) is


Show that f(x) = x1/3 is not differentiable at x = 0.


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


Write an example of a function which is everywhere continuous but fails to differentiable exactly at five points.


Write the points where f (x) = |loge x| is not differentiable.


Let f (x) = |x| and g (x) = |x3|, then


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


Find k, if f(x) =`log (1+3x)/(5x)` for x ≠ 0

                     = k                    for x = 0

is continuous at x = 0. 


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


Find the points of discontinuity , if any for the function : f(x) = `(x^2 - 9)/(sinx - 9)`


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.


Discuss the continuity of the function `f(x) = (3 - sqrt(2x + 7))/(x - 1)` for x ≠ 1

= `-1/3`   for x = 1, at x = 1


If Y = tan-1 `[(cos 2x - sin 2x)/(sin2x + cos 2x)]` then find `(dy)/(dx)`


If f(x) = `(sqrt(2) cos x - 1)/(cot x - 1), x ≠ pi/4` find the value of `"f"(pi/4)`  so that f (x) becomes continuous at x = `pi/4`


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


f(x) = `{{:(|x - 4|/(2(x - 4))",", "if"  x ≠ 4),(0",", "if"  x = 4):}` at x = 4


Given the function f(x) = `1/(x + 2)`. Find the points of discontinuity of the composite function y = f(f(x))


A function f: R → R satisfies the equation f( x + y) = f(x) f(y) for all x, y ∈ R, f(x) ≠ 0. Suppose that the function is differentiable at x = 0 and f′(0) = 2. Prove that f′(x) = 2f(x).


The set of points where the function f given by f(x) = |2x − 1| sinx is differentiable is ______.


The composition of two continuous function is a continuous function.


`lim_("x" -> "x" //4) ("cos x - sin x")/("x"- "x" /4)`  is equal to ____________.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×