English

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

Advertisements
Advertisements

Question

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

Sum
Advertisements

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
  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:

`sqrt(x^2 + sqrt(x^2 + 1)`


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


Differentiate the following w.r.t.x:

`sqrt(cosx) + sqrt(cossqrt(x)`


Differentiate the following w.r.t.x: `(1 + sinx°)/(1 - sinx°)`


Differentiate the following w.r.t.x: `cot(logx/2) - log(cotx/2)`


Differentiate the following w.r.t.x:

`(e^(2x) - e^(-2x))/(e^(2x) + e^(-2x))`


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: `log(sqrt((1 - sinx)/(1 + sinx)))`


Differentiate the following w.r.t.x: `log[4^(2x)((x^2 + 5)/(sqrt(2x^3 - 4)))^(3/2)]`


Differentiate the following w.r.t.x:

`log[a^(cosx)/((x^2 - 3)^3 logx)]`


Differentiate the following w.r.t.x:

y = (25)log5(secx) − (16)log4(tanx) 


Differentiate the following w.r.t. x : cosec–1 (e–x)


Differentiate the following w.r.t. x: 

`sin^-1(sqrt((1 + x^2)/2))`


Differentiate the following w. r. t. x.

cos–1(1 – x2)


Differentiate the following w.r.t. x :

cos3[cos–1(x3)]


Differentiate the following w.r.t. x : `cot^-1[cot(e^(x^2))]`


Differentiate the following w.r.t. x : `"cosec"^-1[1/cos(5^x)]`


Differentiate the following w.r.t. x : `tan^-1[(1 - tan(x/2))/(1 + tan(x/2))]`


Differentiate the following w.r.t. x : `"cosec"^-1[(10)/(6sin(2^x) - 8cos(2^x))]`


Differentiate the following w.r.t. x :

`cos^-1((1 - x^2)/(1 + x^2))`


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


Differentiate the following w.r.t. x : cos–1(3x – 4x3)


Differentiate the following w.r.t. x :

`sin^-1(4^(x + 1/2)/(1 + 2^(4x)))`


Differentiate the following w.r.t. x : `tan^-1((a + btanx)/(b - atanx))`


Differentiate the following w.r.t. x :

`tan^-1((5 -x)/(6x^2 - 5x - 3))`


Differentiate the following w.r.t. x : `(x^5.tan^3 4x)/(sin^2 3x)`


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


Differentiate the following w.r.t. x :

etanx + (logx)tanx 


Differentiate the following w.r.t. x :

(sin x)tanx + (cos x)cotx 


Show that `"dy"/"dx" = y/x` in the following, where a and p are constants : `sec((x^5 + y^5)/(x^5 - y^5))` = a2 


Show that `"dy"/"dx" = y/x` in the following, where a and p are constants : `tan^-1((3x^2 - 4y^2)/(3x^2 + 4y^2))` = a2 


Show that `"dy"/"dx" = y/x` in the following, where a and p are constants : `e^((x^7 - y^7)/(x^7 + y^7)` = a


If y is a function of x and log (x + y) = 2xy, then the value of y'(0) = ______.


Differentiate y = `sqrt(x^2 + 5)` w.r. to x


If f(x) is odd and differentiable, then f′(x) is


Differentiate `cot^-1((cos x)/(1 + sinx))` w.r. to x


Differentiate `tan^-1((8x)/(1 - 15x^2))` w.r. to x


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


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


If x = p sin θ, y = q cos θ, then `dy/dx` = ______ 


Find `(dy)/(dx)`, if x3 + x2y + xy2 + y3 = 81


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


Diffierentiate: `tan^-1((a + b cos x)/(b - a cos x))` w.r.t.x.


If y = log (sec x + tan x), find `dy/dx`.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×