English

Discuss the continuity of the following function at the point(s) or on the interval indicated against them: f(x) =sin2πx3(1-x)2,for x≠1=π2sin2(πx2)3+4cos2(πx2),for x=1} at x = 1

Advertisements
Advertisements

Question

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

f(x) `{:( = (sin^2pix)/(3(1 - x)^2) ",", "for"  x ≠ 1),(= (pi^2sin^2((pix)/2))/(3 + 4cos^2 ((pix)/2)) ",", "for"  x = 1):}}` at x = 1

Sum
Advertisements

Solution

f(1) = `(pi^2sin^2 (pi/2))/(3 + 4cos^2 (pi/2))`

= `(pi^2 xx 1^2)/(3 + 0)`

= `pi^2/3`    ...(1)

`lim_(x -> 1) "f"(x) =  lim_(x -> 1) (sin^2pix)/(3(1 - x)^2`

= `lim_(x -> 1) (sin^2(pi - pix))/(3(1 - x)^2`   ...[∵ sin (π – θ) = sin θ]

= `lim_(x -> 1) [sin{pi(1 - x)}]^2/(3pi^2(1 - x)^2) * pi^2`

= `pi^2/3 [lim_(x -> 1) (sin{pi(1 - x)})/[pi(1 - x))]^2`

= `pi^2/3 xx 1^2  ...[(because x -> 1","  (x - 1) -> 0 "," therefore pi(1 - x) -> 0),("and" lim_(theta -> 0)  sintheta/theta = 1)]`

= `pi^2/3`    ...(2)

From (1) and (2),

`lim_(x -> 1) "f"(x)` = f(1)

∴ f is continuous at x = 1

shaalaa.com
  Is there an error in this question or solution?
Chapter 8: Continuity - MISCELLANEOUS EXERCISE-8 [Page 177]

APPEARS IN

RELATED QUESTIONS

Find all the point of discontinuities of f(x) = [x] on the interval (− 3, 2).


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

f(x)  `{:(= (sqrt(x - 1) - (x - 1)^(1/3))/(x - 2)",",  "for"  x ≠ 2),(= 1/5",",  "for"  x = 2):}}`at x = 2


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

f(x)  `{:(= (x^3 - 8)/(sqrt(x + 2) - sqrt(3x - 2))",",  "for"  x ≠ 2),(= -24",",  "for"  x = 2):}}` at x = 2


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

f(x) `{:(= 4x + 1",",  "for"  x ≤  8/3),(= (59 - 9x)/3 ",",  "for"  x > 8/3):}}  "at"  x = 8/3`


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.


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

f(x) `{:( =(x^2 + 8x - 20)/(2x^2 - 9x + 10)",",  "for"  0 < x < 3","  x ≠ 2),(= 12",",  "for"  x = 2),(= (2 - 2x - x^2)/(x - 4)",",  "for"  3 ≤ x < 4):}}` at x = 2


Identify discontinuities for the following function as either a jump or a removable discontinuity :

f(x) = `(x^2 - 10x + 21)/(x - 7)`


Identify discontinuities for the following function as either a jump or a removable discontinuity :

f(x) `{:(= x^2 - 3x - 2",",  "for"  x < -3),(= 3 + 8x",",  "for"  x > -3):}`


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 become continuous :

f(x) `{:(= 3x + 2",",  "for"  -4 ≤ x ≤-2),(= 2x - 3";",  "for"  -2 < x ≤ 6):}`


If f(x) `{:(= (sin2x)/(5x) - "a"",", "for"  x > 0),(= 4 ",", "for"  x = 0),(= x^2 + "b" - 3",", "for"  x < 0):}}` is continuous at x = 0, find a and b


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?


Discuss the continuity of f(x) at x = `pi/4` where, 

f(x) `{:(= ((sinx + cosx)^3 - 2sqrt(2))/(sin 2x - 1)",", "for"  x ≠ pi/4),(= 3/sqrt(2)",", "for"  x = pi/4):}`


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


Let f(x) = ax + b (where a and b are unknown)

= x2 + 5 for x ∈ R

Find the values of a and b, so that f(x) is continuous at x = 1


Suppose f(x) `{:(= "p"x + 3",", "for"  "a" ≤ x ≤ "b"),(= 5x^2 − "q"",", "for"  "b" < x ≤ "c"):}`

Find the condition on p, q, so that f(x) is continuous on [a, c], by filling in the blanks.

f(b) = ______

`lim_(x -> "b"^+) "f"(x)` = _______

∴ pb + 3 = _______ − q

∴ p = `"_____"/"b"` is the required condition


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) = `(x^2 - 7x + 10)/(x^2 + 2x - 8)`, for x ∈ [– 6, – 3]


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


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

f(x) `{:(= x^2 + 5x + 1"," , "for"  0 ≤ x ≤ 3),(= x^3 + x + 5"," , "for"  3 < x ≤ 6):}`


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

f(x) `{:(= (x^2 + x + 1)/(x + 1)"," , "for"  x ∈ [0, 3)),(=(3x +4)/(x^2 - 5)"," , "for"  x ∈ [3, 6]):}`


Discuss the continuity of the following function at the point or on the interval indicated against them. If the function is discontinuous, identify the type of discontinuity and state whether the discontinuity is removable. If it has a removable discontinuity, redefine the function so that it becomes continuous:

f(x) `{:(= x^2 + 2x + 5"," , "for"  x ≤ 3),( = x^3 - 2x^2 - 5",", "for"  x > 3):}`


Find k if following function is continuous at the point indicated against them:

f(x) `{:(= (45^x - 9^x - 5^x + 1)/(("k"^x - 1)(3^x - 1))",", "for"  x ≠ 0),(= 2/3",", "for"  x = 0):}}` at x = 0


Find f(a), if f is continuous at x = a where,

f(x) = `(1 + cos(pi x))/(pi(1 - x)^2)`, for x ≠ 1 and at a = 1


Find f(a), if f is continuous at x = a where,

f(x) = `(1 - cos[7(x - pi)])/(5(x - pi)^2`, for x ≠ π at a = π


Solve using intermediate value theorem:

Show that 5x − 6x = 0 has a root in [1, 2]


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) = `[tan (pi/4 + x)]^(1/x)`, x ≠ 0 at

= k, x = 0 is continuous x = 0. Then k = ______.


Let f be the function defined by

f(x) = `{{:((x^2 - 1)/(x^2 - 2|x - 1| - 1)",", x ≠ 1),(1/2",", x = 1):}`


For what value of k, the function defined by

f(x) = `{{:((log(1 + 2x)sin^0)/x^2",", "for"  x ≠ 0),(k",", "for"  x = 0):}`

is continuous at x = 0 ?


The function f(x) = x – |x – x2| is ______.


If f(x) = `{{:((sin^3(sqrt(3)).log(1  +  3x))/((tan^-1 sqrt(x))^2(e^(5sqrt(3))  -  1)x)",", x ≠ 0),(                         a",", x = 0):}`

is continuous in [0, 1] then a is equal to ______.


Let `f(x) = (2 - sqrt(x + 4))/(sin 2x), x ≠ 0`. In order that f(x) is continuous at x = 0, f(0) is to be defined as ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×