मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

If x = esin3t, y = ecos3t, then show that dydxdydx=-ylogxxlogy.

Advertisements
Advertisements

प्रश्न

If x = esin3t, y = ecos3t, then show that `dy/dx = -(ylogx)/(xlogy)`.

बेरीज
Advertisements

उत्तर

x = esin3t, y = ecos3t 
∴ log x = logesin3t, logy = logecos3t
∴ log x = (sin 3t)(log e), log y = (cos 3t)(log e)
∴ log x = sin 3t, log y = cos 3t ...(1) ... [∵ log e = 1]
Differentiating both sides w.r.t. t, we get
`(1)/x.dx/dt = d/dt(sin3t) = cos3t.d/dt(3t)`
= cos 3t x 3

= 3 cos 3t
and
`(1)/y.dy/dt = d/dt(cos 3t) = -sin3t.d/dx(3t)`
= – sin 3t x 3

= – 3 sin 3t
∴ `dx/dt = 3x cos 3t and dy/dt"= -3y sin 3t`

∴ `dy/dx = ((dy/dt))/((dx/dt)`

= `(-3y sin 3t)/(3x cos 3t)`

= `(-y sin 3t)/(x cos 3t)`

= `(-y log x)/(x log y)`.                     ...[By (1)]

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 1: Differentiation - Exercise 1.4 [पृष्ठ ४८]

APPEARS IN

संबंधित प्रश्‍न

Differentiate the function with respect to x.

(log x)cos x


Differentiate the function with respect to x.

(x + 3)2 . (x + 4)3 . (x + 5)4


Find `bb(dy/dx)` for the given function:

xy = `e^((x - y))`


Find the derivative of the function given by f(x) = (1 + x) (1 + x2) (1 + x4) (1 + x8) and hence find f′(1).


Differentiate the function with respect to x:

xx + xa + ax + aa, for some fixed a > 0 and x > 0


If y = `e^(acos^(-1)x)`, −1 ≤ x ≤ 1, show that `(1- x^2) (d^2y)/(dx^2) -x dy/dx - a^2y = 0`.


Find `(dy)/(dx) , if y = sin ^(-1) [2^(x +1 )/(1+4^x)]`


Differentiate  
log (1 + x2) w.r.t. tan-1 (x)


Find `"dy"/"dx"` , if `"y" = "x"^("e"^"x")`


xy = ex-y, then show that  `"dy"/"dx" = ("log  x")/("1 + log x")^2`


If `"x"^(5/3) . "y"^(2/3) = ("x + y")^(7/3)` , the show that `"dy"/"dx" = "y"/"x"`


 Solve the following differential equation: (3xy + y2) dx + (x2 + xy) dy = 0 


If ey = yx, then show that `"dy"/"dx" = (logy)^2/(log y - 1)`.


If x = `asqrt(secθ - tanθ), y = asqrt(secθ + tanθ), "then show that" "dy"/"dx" = -y/x`.


If x = a cos3t, y = a sin3t, show that `"dy"/"dx" = -(y/x)^(1/3)`.


If x = 2cos4(t + 3), y = 3sin4(t + 3), show that `"dy"/"dx" = -sqrt((3y)/(2x)`.


Find the second order derivatives of the following : log(logx)


If y = `log(x + sqrt(x^2 + a^2))^m`, show that `(x^2 + a^2)(d^2y)/(dx^2) + x "d"/"dx"` = 0.


Find the nth derivative of the following: log (ax + b)


Find the nth derivative of the following : log (2x + 3)


If y = A cos (log x) + B sin (log x), show that x2y2 + xy1 + y = 0.


If y = `log[sqrt((1 - cos((3x)/2))/(1 +cos((3x)/2)))]`, find `("d"y)/("d"x)`


If y = `log[4^(2x)((x^2 + 5)/sqrt(2x^3 - 4))^(3/2)]`, find `("d"y)/("d"x)`


Derivative of loge2 (logx) with respect to x is _______.


If y = `{f(x)}^{phi(x)}`, then `dy/dx` is ______ 


`d/dx(x^{sinx})` = ______ 


`"d"/"dx" [(cos x)^(log x)]` = ______.


Derivative of `log_6`x with respect 6x to is ______


`2^(cos^(2_x)`


`lim_("x" -> 0)(1 - "cos x")/"x"^2` is equal to ____________.


If `"f" ("x") = sqrt (1 + "cos"^2 ("x"^2)), "then the value of f'" (sqrtpi/2)` is ____________.


If `"y" = "e"^(1/2log (1 +  "tan"^2"x")), "then"  "dy"/"dx"` is equal to ____________.


If y `= "e"^(3"x" + 7), "then the value" |("dy")/("dx")|_("x" = 0)` is ____________.


If `log_10 ((x^2 - y^2)/(x^2 + y^2))` = 2, then `dy/dx` is equal to ______.


If y = `log(x + sqrt(x^2 + 4))`, show that `dy/dx = 1/sqrt(x^2 + 4)`


The derivative of log x with respect to `1/x` is ______.


Find the derivative of `y = log x + 1/x` with respect to x.


If xy = yx, then find `dy/dx`


If \[y=x^x+x^{\frac{1}{x}}\] then \[\frac{\mathrm{d}y}{\mathrm{d}x}\] is equal to


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×