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

If f(x) =sin2x5x-a,for x>0=4,for x=0=x2+b-3,for x<0} is continuous at x = 0, find a and b

Advertisements
Advertisements

प्रश्न

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

बेरीज
Advertisements

उत्तर

f(x) is continuous at x = 0

∴ `lim_(x -> 0^+) "f"(x)` = f(0)

∴ `lim_(x -> 0^+) ((sin2x)/(5x) - "a")` = 4

∴ `lim_(x -> 0^+) (sin 2x)/(5x) - lim_(x -> 0^+) "a"` = 4

∴ `1/5 lim_(x -> 0^+) (sin2x)/(2x) xx (2) - lim_(x -> 0^+) "a"` = 4

∴ `1/5 (1) (2) - "a"` = 4     ...`[(because  x -> 0","  2x -> 0),(lim_(x -> 0^+) sintheta/theta = 1)]`

∴ `2/5 - "a"` = 4

∴ `2/5 - 4` = a

∴ a = `-18/5`

Also, `lim_(x -> 0^+) "f"(x)` = f(0)

∴ `lim_(x -> 0^+) (x^2 + "b" - 3)` = 4

∴ b – 3 = 4

∴ b = 7

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 8: Continuity - EXERCISE 8.1 [पृष्ठ १७४]

APPEARS IN

संबंधित प्रश्‍न

Examine the continuity of f(x) = x3 + 2x2 − 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


Examine whether the function is continuous at the points indicated against them :

f(x) `{:(= x/(tan3x) + 2",",   "for"  x < 0),(= 7/3",",  "for"  x ≥ 0):}}  "at"  x = 0`


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) = `(x^2 - 1)/(x^3 + 1)` for x ≠ – 1


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


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

f(x) = `((3 - 8x)/(3 - 2x))^(1/x)`, for 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) `{:(= (24^x - 8^x - 3^x + 1)/(12^x - 4^x - 3^x + 1)",",  "for"  x ≠ 0), (= "k"",",  "for"  x = 0):}}` is continuous at x = 0, find k


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 2x3 − x − 16 = 0 between 2 and 3.


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


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:

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


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]):}`


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):}`


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):}`


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


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) = `{((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) = `{:{(tan^-1|x|; "when"  x ≠ 0), (pi/4;  "when"  x = 0):}`, then ______ 


If f(x) is continuous at x = 3, where

f(x) = ax + 1, for x ≤ 3

= bx + 3, for x > 3 then.


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

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


Let f : [-1, 2] → [0, ∞] be a continuous function such that f(x) = f(1 - x) ∀ x ∈ [-1, 2].

Let R1 = `int_-1^2 xf(x) dx` and R2 be the area of the region bounded by y = f(x), x = -1, x = 2 and the X-axis. Then, ______


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


If f(x) = `{{:((3 sin πx)/(5x),",", x ≠ 0),(2k,",", x = 0):}`

is continuous at x = 0, then the value of k is ______.


`lim_(x rightarrow 0) (e^(x^2) - cosx)/x^2` is equal to ______.


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


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×