मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता ११ वी

Test the continuity of the following function at the point or interval indicated against them : f(x) =(27-2x)13-39-3(243+5x)15, for x≠0=2, for x=0} at x = 0.

Advertisements
Advertisements

प्रश्न

Test the continuity of the following function at the point or interval indicated against them :

f(x) `{:(= ((27 - 2x)^(1/3) - 3)/(9 - 3(243 + 5x)^(1/5))",",  "for"  x ≠ 0),(= 2",",  "for"  x = 0):}}` at x = 0.

बेरीज
Advertisements

उत्तर

f(0) = 2     ...(Given)

`lim_(x -> 0) "f"(x) =  lim_(x -> 0) ((27 - 2x)^(1/3) - 3)/(9 - 3(243 + 5x)^(1/5))`

= `lim_(x -> 0) ((27 - 2x)^(1/3) - 3)/(-3[(243 + 5x)^(1/5) - 3]`

= `(-1)/(3)  lim_(x -> 0) ((27 - 2x)^(1/3) - (27)^(1/3))/((243 + 5x)^(1/5) - (243)^(1/5))`

= `(-1)/(3) lim_(x -> 0)  (((27 - 2x)^(1/3) - 27^(1/3))/((27 - 2x) - 27) xx [(27 - 2x) - 27])/(((243 + 5x)^(1/5) - (243)^(1/5))/((243 + 5x) - 243) xx [(243 + 5x) - 243])`

...`[("As"  x -> 0"," -2x -> 0 and 5x -> 0),(therefore (27 - 2x) - 27 -> 0 and (243 + 5x) - 243 -> 0),(therefore (27 - 2x) - 27 ≠ 0 and (243 + 5x) - 243 ≠ 0)]`

= `(-1)/(3) (lim_(x -> 0) ((27 - 2x)^(1/3) - 27^(1/3))/((27 - 2x) - 27) xx (-2x))/(lim_(x -> 0) ((243 + 5x)^(1/3) - (243)^(1/5))/((243 + 5x) - 243) xx (5x)`

= `(-1)/(3) xx (-2)/(5) xx (lim_(x -> 0)((27 - 2x)^(1/3) - 27^(1/3))/((27 - 2x) - 27))/(lim_(x -> 0) ((243 + 5x)^(1/5) - (243)^(1/5))/((243 + 5x) - 243)`  ...[∵  x  → 0, x ≠ 0]

= `2/15 xx (1/3(27)^((-2)/3))/(1/5(243)^((-4)/5))  ...[because  lim_(x -> "a") (x^"n" - "a"^"n")/(x - "a") = "na"^("n" - 1)]`

= `2/15 xx 5/3 xx ((3^3)^((-2)/3))/((3^5)^((-4)/5))`

= `2/9 xx (3)^(-2)/(3)^(-4)`

= `2/9 xx (3)^2`

= 2

∴ `lim_(x -> 0) "f"(x)` = f(0)

∴ f(x) is continuous at x = 0

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 8: Continuity - EXERCISE 8.1 [पृष्ठ १७३]

APPEARS IN

संबंधित प्रश्‍न

Examine whether the function is continuous at the points indicated against them:
f(x) = x3 − 2x + 1,         for x ≤ 2
      = 3x − 2,                 for x > 2, at x = 2


Examine whether the function is continuous at the points indicated against them:
f(x) = `(x^2 + 18x - 19)/(x - 1)`        for x ≠ 1

      = 20                               for x = 1, at x = 1


Show that following function have continuous extension to the point where f(x) is not defined. Also find the extension :

f(x) = `(1 - cos2x)/sinx`, for x ≠ 0


The following function has a removable discontinuity? If it has a removable discontinuity, redefine the function so that it becomes continuous :

f(x) `{:(=("e"^(5sinx) - "e"^(2x))/(5tanx - 3x)",",   "for"  x ≠ 0),(= 3/4",",   "for"  x = 0):}}` at x = 0


The following function has a removable discontinuity? If it has a removable discontinuity, redefine the function so that it become continuous :

f(x) `{:(= log_((1 + 3x)) (1 + 5x)",", "for"  x > 0),(=(32^x - 1)/(8^x - 1)",",  "for"  x < 0):}}` at x = 0


The following function has a removable discontinuity? If it has a removable discontinuity, redefine the function so that it become continuous :

f(x) `{:(= (x^3 - 8)/(x^2 - 4)",",  "for"  x > 2),(= 3",",  "for"  x = 2),(= ("e"^(3(x - 2)^2 - 1))/(2(x - 2)^2) ",",  "for"  x < 2):}`


If f(x) = `(4^(x - π) + 4^(π - x) - 2)/(x - π)^2` for x ≠ π, is continuous at x = π, then find f(π).


For what values of a and b is the function

f(x) `{:(= (x^2 - 4)/(x - 2)",", "for"  x < 2),(= "a"x^2 - "b"x + 3",", "for"  2 ≤ x < 3),(= 2x - "a" + "b"",", "for"  x ≥ 3):}}` continuous for every x on R?


Show that there is a root for the equation 2x3 − x − 16 = 0 between 2 and 3.


Show that there is a root for the equation x3 − 3x = 0 between 1 and 2.


Select the correct answer from the given alternatives:

f(x) = `{:(= (2^(cotx) - 1)/(pi - 2x)",", "for"  x ≠ pi/2),(= log sqrt(2)",", "for"  x = pi/2):}`


Select the correct answer from the given alternatives:

f(x) `{:(= (32^x - 8^x - 4^x + 1)/(4^x - 2^(x + 1) + 1)",", "for"  x ≠ 0),(= "k""," , "for"  x = 0):}` is continuous at x = 0, then value of ‘k’ is


Select the correct answer from the given alternatives:

If f(x) = `((4 + 5x)/(4 - 7x))^(4/x)`, for x ≠ 0 and f(0) = k, is continuous at x = 0, then k is


Select the correct answer from the given alternatives:

If f(x) = [x] for x ∈ (–1, 2) then f is discontinuous at


Discuss the continuity of the following function at the point(s) or on the interval indicated against them:

f(x) `{:(= 2x^2 - 2x + 5",", "for"  0 ≤ x ≤ 2),(= (1 - 3x - x^2)/(1 - x) "," , "for"  2 < x < 4),(= (x^2 - 25)/(x - 5)",", "for"  4 ≤ x ≤ 7 and x ≠ 5),(= 7",", "for"  x = 5):}`


Discuss the continuity of the following function at the point(s) or on the interval indicated against them:

f(x) `{:(= (|x + 1|)/(2x^2 + x - 1)",", "for"  x ≠ -1),(= 0",", "for"  x = -1):}}` at x = – 1


Discuss the continuity of the following function at the point(s) or on the interval indicated against them:

f(x) = [x + 1] for x ∈ [−2, 2)

Where [*] is greatest integer function.


Discuss the continuity of the following function at the point(s) or on the interval indicated against them:

f(x) `{:(= 2x^2 + x + 1",", "for"  |x - 3| ≥ 2),(= x^2 + 3",", "for"  1 < x < 5):}`


Identify discontinuity for the following function as either a jump or a removable discontinuity on their respective domain:

f(x) `{:(= x^2 + x - 3,","  "for"  x ∈ [ -5, -2)),(= x^2 - 5,","  "for"  x ∈ (-2, 5]):}`


Find a and b if following function is continuous at the point or on the interval indicated against them:

f(x) `{:(= (4tanx + 5sinx)/("a"^x - 1)",", "for"  x < 0),(= (9)/(log2)",", "for"  x = 0),(= (11x + 7x*cosx)/("b"^x - 1)",", "for"  x > 0):}`


Solve using intermediate value theorem:

Show that x3 − 5x2 + 3x + 6 = 0 has at least two real root between x = 1 and x = 5


If f(x) = `{(8-6x;   0<x≤2), (4x-12;    2<x≤3),(2x+10;    3<x≤6):}` then f(x) is ______ 


If f(x) `= sqrt(4 + "x" - 2)/"x", "x" ne 0` be continuous at x = 0, then f(0) = ______.


If f(x) = `1/(1 - x)`, the number of points of discontinuity of f{f[f(x)]} is ______.


If the function f(x) = `[tan(π/4 + x)]^(1/x)` for x ≠ 0 is = K for x = 0 continuous at x = 0, then K = ?


If f(x) = `{{:(log(sec^2 x)^(cot^2x)",", "for"  x ≠ 0),(K",", "for"  x = 0):}`

is continuous at x = 0, then K is ______.


If \[\mathrm{f}(x)= \begin{cases} \mathrm{m}x+1, & x\leqslant\frac{\pi}{2} \\ \\ \mathrm{sin}x+\mathrm{n}, & x>\frac{\pi}{2} & \end{cases}\], is continuous at \[x=\frac{\pi}{2},( \begin{array} {c}\mathrm{m,n\in\mathbb{Z}} \end{array})\] then


If \[f\] is defined on the closed interval \[[a,b]\], which condition establishes continuity at the right endpoint \[b\]?


When is \[f(x)\] non-removable discontinuous at \[x=a\]?


What is the graphical meaning of a function being continuous at a point?


For \[f(x)=\begin{cases}1,&x\leq0\\2,&x>0\end{cases}\], why is \[f\] discontinuous at \[x=0\]?


For which values is the identity function \[f(x)=x\] continuous?


Which statement about polynomial functions is correct?


For \[f(x)=x^2\], what verifies continuity at \[x=0\]?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×