हिंदी

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.

योग
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
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 8: Continuity - EXERCISE 8.1 [पृष्ठ १७३]

APPEARS IN

बालभारती Mathematics and Statistics 2 (Arts and Science) [English] Standard 11 Maharashtra State Board
अध्याय 8 Continuity
EXERCISE 8.1 | Q 5) (iv) | पृष्ठ १७३

संबंधित प्रश्न

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


Examine the continuity of `f(x) = {:((x^2 - 9)/(x  - 3)",",  "for"  x ≠ 3),(=8",",  "for"  x = 3):}}` at x = 3.


Discuss the continuity of the function f(x) = |2x + 3|, at x = `(−3)/(2)`


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 the discontinuity for the following function as either a jump or a removable discontinuity.

f(x) `{:(= x^2 + 3x - 2",",  "for"  x ≤ 4),(= 5x + 3",",  "for"  x > 4):}`


Discuss the continuity of the following function at the point indicated against them :

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


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).


If f(x)  `{:(= (5^x + 5^(-x) - 2)/(x^2)"," , "for"  x ≠ 0),(= k",",  "for"  x = 0):}}` is continuous at x = 0, find k


Discuss the continuity of f on its domain, where f(x) `{:(= |x + 1|",", "for"  -3 ≤ x ≤ 2),(= |x - 5|",", "for"  2 < x ≤ 7):}`.


Select the correct answer from the given alternatives:

If f(x) = `(1 - sqrt(2) sinx)/(pi - 4x), "for"  x ≠ pi/4` is continuous at x = `pi/4`, then `"f"(pi/4)` =


Select the correct answer from the given alternatives:

If f(x) = `((sin2x)tan5x)/("e"^(2x) - 1)^2`, for x ≠ 0 is continuous at x = 0, then f(0) is


Select the correct answer from the given alternatives:

If f(x) `{:(= "a"x^2 + "b"x + 1",", "for"  |x −1| ≥ 3), (= 4x + 5",", "for"  -2 < x < 4):}` is continuous everywhere then,


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


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


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 + 3)(x^2 - 6x + 8))/(x^2 - x - 12)`


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) `{:(= ((5x - 8)/(8 - 3x))^(3/(2x - 4))",", "for"  x ≠ 2),(= "k"",", "for"  x = 2):}}` at x = 2


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


If f(x) = `{((x^4 - 1/81)/(x^3 - 1/27), x ≠ 1/3), (k, x = 1/3):}` is continuous at x = `1/3`, then the value of k is ______


If f(x) = `{{:(tanx/x + secx",",   x ≠ 0),(2",",  x = 0):}`, then ______.


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


Let f be the function defined by

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


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 f(x) = `{{:(x, "for"  x ≤ 0),(0,
"for"  x > 0):}`, then f(x) at x = 0 is ______.


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 ?


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 ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×