English

Cos-1(sinx+cosx2),-π4<x<π4

Advertisements
Advertisements

Question

`cos^-1 ((sinx + cosx)/sqrt(2)), (-pi)/4 < x < pi/4`

Sum
Advertisements

Solution

Let y = `cos^-1 ((sin x + cosx)/sqrt(x))`

= `cos^-1 [1/sqrt(2) sin x + 1/sqrt(2) cos x]`

= `cos^-1 [sin  pi/4 sin x + cos  pi/4 * cos x]`

= `cos^-1 [cos(pi/4 - x)]`

y = `pi/4 - x`  ......`[∵ - pi/4 < x < pi/4]`

Differentiating both sides w.r.t. x

`"dy"/"dx"` = – 1

shaalaa.com
  Is there an error in this question or solution?
Chapter 5: Continuity And Differentiability - Exercise [Page 110]

APPEARS IN

NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 5 Continuity And Differentiability
Exercise | Q 37 | Page 110

RELATED QUESTIONS

Differentiate the function with respect to x.

sin (x2 + 5)


Differentiate the function with respect to x. 

cos x3 . sin2 (x5)


Differentiate the function with respect to x. 

`2sqrt(cot(x^2))`


Prove that the function f given by f(x) = |x − 1|, x ∈ R is not differentiable at x = 1.


Differentiate the function with respect to x:

(3x2 – 9x + 5)9


Differentiate the function with respect to x:

`(5x)^(3cos 2x)`


Find `dy/dx`, if y = 12 (1 – cos t), x = 10 (t – sin t), `-pi/2 < t < pi/2`.


Does there exist a function which is continuos everywhere but not differentiable at exactly two points? Justify your answer?


If y = `[(f(x), g(x), h(x)),(l, m,n),(a,b,c)]`, prove that `dy/dx = |(f'(x), g'(x), h'(x)),(l,m, n),(a,b,c)|`.


Discuss the continuity and differentiability of the 

\[f\left( x \right) = \left| x \right| + \left| x - 1 \right| \text{in the interval} \left( - 1, 2 \right)\]

If sin y = xsin(a + y) prove that `(dy)/(dx) = sin^2(a + y)/sin a`


Let f(x) = x|x|, for all x ∈ R. Discuss the derivability of f(x) at x = 0


If y = tanx + secx, prove that `("d"^2y)/("d"x^2) = cosx/(1 - sinx)^2`


Differential coefficient of sec (tan–1x) w.r.t. x is ______.


If u = `sin^-1 ((2x)/(1 + x^2))` and v = `tan^-1 ((2x)/(1 - x^2))`, then `"du"/"dv"` is ______.


COLUMN-I COLUMN-II
(A) If a function
f(x) = `{((sin3x)/x, "if"  x = 0),("k"/2",",  "if"  x = 0):}`
is continuous at x = 0, then k is equal to
(a) |x|
(B) Every continuous function is differentiable (b) True
(C) An example of a function which is continuous
everywhere but not differentiable at exactly one point
(c) 6
(D) The identity function i.e. f (x) = x ∀ ∈x R
is a continuous function
(d) False

`sin sqrt(x) + cos^2 sqrt(x)`


sinn (ax2 + bx + c)


sinx2 + sin2x + sin2(x2)


(sin x)cosx 


sinmx . cosnx


`sec^-1 (1/(4x^3 - 3x)), 0 < x < 1/sqrt(2)`


`tan^-1 ((3"a"^2x - x^3)/("a"^3 - 3"a"x^2)), (-1)/sqrt(3) < x/"a" < 1/sqrt(3)`


`tan^-1 ((sqrt(1 + x^2) + sqrt(1 - x^2))/(sqrt(1 + x^2) - sqrt(1 - x^2))), -1 < x < 1, x ≠ 0`


If y = `sqrt(sinx + y)`, then `"dy"/"dx"` is equal to ______.


The differential coefficient of `"tan"^-1 ((sqrt(1 + "x") - sqrt (1 - "x"))/(sqrt (1+ "x") + sqrt (1 - "x")))` is ____________.


The rate of increase of bacteria in a certain culture is proportional to the number present. If it doubles in 5 hours then in 25 hours, its number would be


If sin y = x sin (a + y), then value of dy/dx is


If `ysqrt(1 - x^2) + xsqrt(1 - y^2)` = 1, then prove that `(dy)/(dx) = - sqrt((1 - y^2)/(1 - x^2))`


A particle is moving on a line, where its position S in meters is a function of time t in seconds given by S = t3 + at2 + bt + c where a, b, c are constant. It is known that at t = 1 seconds, the position of the particle is given by S = 7 m. Velocity is 7 m/s and acceleration is 12 m/s2. The values of a, b, c are ______.


If f(x) = `{{:((sin(p  +  1)x  +  sinx)/x,",", x < 0),(q,",", x = 0),((sqrt(x  +  x^2)  -  sqrt(x))/(x^(3//2)),",", x > 0):}`

is continuous at x = 0, then the ordered pair (p, q) is equal to ______.


If f(x) = | cos x |, then `f((3π)/4)` is ______.


Prove that the greatest integer function defined by f(x) = [x], 0 < x < 3 is not differentiable at x = 1 and x = 2.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×