English

If y = tan-1[1+cosx1-cosx], find dddydx - Mathematics and Statistics

Advertisements
Advertisements

Question

If y = `tan^-1[sqrt((1 + cos x)/(1 - cos x))]`, find `("d"y)/("d"x)`

Sum

Solution

`tan^-1[sqrt((1 + cos x)/(1 - cos x))]`

Put `1 + cos x = 2 cos^2  x/2`

`1 - cos x = 2 sin^2  x/2`

∵ `cos x = 2 cos^2  x/2 - 1 = 1 - 2 sin^2  x/2`

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

= `tan^-1 [sqrt(cot^2(x/2))]`

= `tan^-1 [cot(x/2)]`

= `tan^-1 [tan(pi/2- x/2)]      ...[cot theta = tan(pi/2 - theta)]`

= `pi/2 - x/2          ...[tan^-1 (tan theta) = theta]`

Differentiating w. r. t. x, we get

`("d"y)/("d"x) = "d"/("d"x) pi/2 -  "d"/("d"x) x/2`

∴ `("d"y)/("d"x) = 0 - 1/2 "d"/("d"x) x`

∴ `("d"y)/("d"x) = -1/2`

shaalaa.com
Differentiation
  Is there an error in this question or solution?
Chapter 2.1: Differentiation - Short Answers I

RELATED QUESTIONS

Differentiate the following w.r.t.x:

(x3 – 2x – 1)5


Differentiate the following w.r.t.x:

`(sqrt(3x - 5) - 1/sqrt(3x - 5))^5`


Differentiate the following w.r.t.x: `5^(sin^3x + 3)`


Differentiate the following w.r.t.x: `"cosec"(sqrt(cos x))`


Differentiate the following w.r.t.x: cos2[log(x2 + 7)]


Differentiate the following w.r.t.x: `sinsqrt(sinsqrt(x)`


Differentiate the following w.r.t.x: `log_(e^2) (log x)`


Differentiate the following w.r.t.x: [log {log(logx)}]2


Differentiate the following w.r.t.x:

`(x^3 - 5)^5/(x^3 + 3)^3`


Differentiate the following w.r.t.x: (1 + sin2 x)2 (1 + cos2 x)3 


Differentiate the following w.r.t.x: log[tan3x.sin4x.(x2 + 7)7]


Differentiate the following w.r.t.x:

`log(sqrt((1 + cos((5x)/2))/(1 - cos((5x)/2))))`


Differentiate the following w.r.t.x:

y = (25)log5(secx) − (16)log4(tanx) 


Differentiate the following w.r.t. x : `tan^-1(sqrt(x))`


Differentiate the following w.r.t. x :

cos3[cos–1(x3)]


Differentiate the following w.r.t. x : `cos^-1(sqrt((1 + cosx)/2))`


Differentiate the following w.r.t. x : `tan^-1((cos7x)/(1 + sin7x))`


Differentiate the following w.r.t. x : `sin^-1(2xsqrt(1 - x^2))`


Differentiate the following w.r.t. x :

`sin^(−1) ((1 − x^3)/(1 + x^3))`


Differentiate the following w.r.t.x:

`cot^-1((1 + 35x^2)/(2x))`


Differentiate the following w.r.t. x : `root(3)((4x - 1)/((2x + 3)(5 - 2x)^2)`


Differentiate the following w.r.t. x : `((x^2 + 2x + 2)^(3/2))/((sqrt(x) + 3)^3(cosx)^x`


Differentiate the following w.r.t. x : (sin x)x 


Differentiate the following w.r.t. x:

`x^(x^x) + e^(x^x)`


Differentiate the following w.r.t. x :

(sin x)tanx + (cos x)cotx 


Differentiate y = etanx w.r. to x


If y = sin−1 (2x), find `("d"y)/(""d"x)` 


If y = `"e"^(1 + logx)` then find `("d"y)/("d"x)` 


If y = `sin^-1[("a"cosx - "b"sinx)/sqrt("a"^2 + "b"^2)]`, then find `("d"y)/("d"x)`


If y = `1 + x + x^2/(2!) + x^3/(3!) + x^4/(4!) + .....,` then `(d^2y)/(dx^2)` = ______


A particle moves so that x = 2 + 27t - t3. The direction of motion reverses after moving a distance of ______ units.


If f(x) = `(3x + 1)/(5x - 4)` and t = `(5 + 3x)/(x - 4)`, then f(t) is ______ 


The differential equation of the family of curves y = `"ae"^(2(x + "b"))` is ______.


If x2 + y2 - 2axy = 0, then `dy/dx` equals ______ 


The volume of a spherical balloon is increasing at the rate of 10 cubic centimetre per minute. The rate of change of the surface of the balloon at the instant when its radius is 4 centimetres, is ______


Differentiate `tan^-1 (sqrt((3 - x)/(3 + x)))` w.r.t. x.


If `cos((x^2 - y^2)/(x^2 + y^2))` = log a, show that `dy/dx = y/x`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×