English

If y = tan–1x, find ddxd2ydx2 in terms of y alone.

Advertisements
Advertisements

Question

If y = tan–1x, find `("d"^2y)/("dx"^2)` in terms of y alone.

Sum
Advertisements

Solution

Given that: y = tan–1x

⇒ x = tan y

Differentiating both sides w.r.t. y

`"dx"/"dy"` = sec2y

⇒ `"dy"/'dx" = 1/(sec^2y)` = cos2y

Again differentiating both sides w.r.t. x

⇒ `"d"/"dx"("dy"/"dx") = "d"/"dx"(cos^2y)`

⇒ `("d"^2y)/("dx"^2) = 2cos y * "d"/"dx" (cos y)`

⇒ `("d"^2y)/("dx"^2) = 2cos y(- siny) * "dy"/"dx"` 

⇒ `("d"^2y)/("dx"^2) = - 2sin y cos y * cos^2 y`

∴ `("d"^2y)/("dx"^2)` = – 2 sin y cos3y

shaalaa.com
  Is there an error in this question or solution?
Chapter 5: Continuity And Differentiability - Exercise [Page 111]

APPEARS IN

NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 5 Continuity And Differentiability
Exercise | Q 64 | Page 111

Video TutorialsVIEW ALL [2]

RELATED QUESTIONS

If x = a sin t and `y = a (cost+logtan(t/2))` ,find `((d^2y)/(dx^2))`


If y=2 cos(logx)+3 sin(logx), prove that `x^2(d^2y)/(dx2)+x dy/dx+y=0`


If x cos(a+y)= cosy then prove that `dy/dx=(cos^2(a+y)/sina)`

Hence show that `sina(d^2y)/(dx^2)+sin2(a+y)(dy)/dx=0`


Find the second order derivative of the function.

x20


Find the second order derivative of the function.

log x


Find the second order derivative of the function.

x3 log x


Find the second order derivative of the function.

ex sin 5x


Find the second order derivative of the function.

tan–1 x


If y = 5 cos x – 3 sin x, prove that `(d^2y)/(dx^2) + y = 0`.


If y = cos–1 x, find `(d^2y)/dx^2` in terms of y alone.


If y = (tan–1 x)2, show that (x2 + 1)2 y2 + 2x (x2 + 1) y1 = 2


If x7 . y9 = (x + y)16 then show that `"dy"/"dx" = "y"/"x"`


If `x^3y^5 = (x + y)^8` , then show that `(dy)/(dx) = y/x`


Find `("d"^2"y")/"dx"^2`, if y = `sqrt"x"`


Find `("d"^2"y")/"dx"^2`, if y = `"e"^((2"x" + 1))`.


Find `("d"^2"y")/"dx"^2`, if y = 2at, x = at2


If x2 + 6xy + y2 = 10, then show that `("d"^2y)/("d"x^2) = 80/(3x + y)^3`


`sin xy + x/y` = x2 – y


sec(x + y) = xy


tan–1(x2 + y2) = a


(x2 + y2)2 = xy


If ax2 + 2hxy + by2 + 2gx + 2fy + c = 0, then show that `"dy"/"dx" * "dx"/"dy"` = 1 


The derivative of cos–1(2x2 – 1) w.r.t. cos–1x is ______.


If y = 5 cos x – 3 sin x, then `("d"^2"y")/("dx"^2)` is equal to:


If x2 + y2 + sin y = 4, then the value of `(d^2y)/(dx^2)` at the point (–2, 0) is ______.


If y = `sqrt(ax + b)`, prove that `y((d^2y)/dx^2) + (dy/dx)^2` = 0.


If x = A cos 4t + B sin 4t, then `(d^2x)/(dt^2)` is equal to ______.


Read the following passage and answer the questions given below:

The relation between the height of the plant ('y' in cm) with respect to its exposure to the sunlight is governed by the following equation y = `4x - 1/2 x^2`, where 'x' is the number of days exposed to the sunlight, for x ≤ 3.

  1. Find the rate of growth of the plant with respect to the number of days exposed to the sunlight.
  2. Does the rate of growth of the plant increase or decrease in the first three days? What will be the height of the plant after 2 days?

`"Find"  (d^2y)/(dx^2)  "if"  y=e^((2x+1))`


Find `(d^2y)/dx^2 if, y = e^((2x + 1))`


Find `(d^2y)/dx^2` if, y = `e^(2x +1)`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×