मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी वाणिज्य (इंग्रजी माध्यम) इयत्ता १२ वी

If log (x + y) = log (xy) + a then show that, dydxyxdydx=-y2x2. - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

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

बेरीज

उत्तर

log (x + y) = log (xy) + a

∴ log (x + y) = log x + log y + a

Differentiating both sides w.r.t. x, we get

`1/("x + y")*"d"/"dx" ("x + y") = 1/"x" + 1/"y" * "dy"/"dx"`

∴ `1/("x + y") (1 + "dy"/"dx") = 1/"x" + 1/"y" * "dy"/"dx"`

∴ `"dy"/"dx" (1/"y" - 1/("x + y")) = 1/("x + y") - 1/"x"`

∴ `"dy"/"dx" ["x"/("y"("x + y"))] = (-"y")/("x"("x + y"))`

∴ `"dy"/"dx" = - "y"^2/"x"^2`

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 3: Differentiation - EXERCISE 3.4 [पृष्ठ ९५]

APPEARS IN

व्हिडिओ ट्यूटोरियलVIEW ALL [3]

संबंधित प्रश्‍न

Find `dy/dx` in the following:

2x + 3y = sin y


Find `dy/dx` in the following:

sin2 x + cos2 y = 1


if `(x^2 + y^2)^2 = xy` find `(dy)/(dx)`


If  \[f\left( x \right) = x^3 + 7 x^2 + 8x - 9\] 

, find f'(4).


Write the derivative of f (x) = |x|3 at x = 0.


Let \[f\left( x \right)\begin{cases}a x^2 + 1, & x > 1 \\ x + 1/2, & x \leq 1\end{cases}\] . Then, f (x) is derivable at x = 1, if 


Find `"dy"/"dx"` ; if y = cos-1 `("2x" sqrt (1 - "x"^2))`


Differentiate e4x + 5 w.r..t.e3x


Differentiate tan-1 (cot 2x) w.r.t.x.


If x = tan-1t and y = t3 , find `(dy)/(dx)`.


Find `"dy"/"dx"`, if : x = `sqrt(a^2 + m^2), y = log(a^2 + m^2)`


Find `"dy"/"dx"` if : x = cosec2θ, y = cot3θ at θ= `pi/(6)`


Differentiate `tan^-1((x)/(sqrt(1 - x^2))) w.r.t. sec^-1((1)/(2x^2 - 1))`.


Differentiate `tan^-1((cosx)/(1 + sinx)) w.r.t. sec^-1 x.`


Find `(d^2y)/(dx^2)` of the following : x = a(θ – sin θ), y = a(1 – cos θ)


If x = cos t, y = emt, show that `(1 - x^2)(d^2y)/(dx^2) - x"dy"/"dx" - m^2y` = 0.


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


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


Choose the correct option from the given alternatives :

If f(x) = `sin^-1((4^(x + 1/2))/(1 + 2^(4x)))`, which of the following is not the derivative of f(x)?


Choose the correct option from the given alternatives :

If `xsqrt(y + 1) + ysqrt(x + 1) = 0 and x ≠ y, "then" "dy"/"dx"` = ........


If y `tan^-1(sqrt((a - x)/(a +  x)))`, where – a < x < a, then `"dy"/"dx"` = .........


Choose the correct option from the given alternatives :

If y = `a cos (logx) and "A"(d^2y)/(dx^2) + "B""dy"/"dx" + "C"` = 0, then the values of A, B, C are


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


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


If sin y = x sin (a + y), then show that `"dy"/"dx" = (sin^2(a + y))/(sina)`.


If y = Aemx + Benx, show that y2 – (m + n)y1 + mny = 0.


Solve the following:

If `"x"^5 * "y"^7 = ("x + y")^12` then show that, `"dy"/"dx" = "y"/"x"`


Choose the correct alternative.

If `"x"^4."y"^5 = ("x + y")^("m + 1")` then `"dy"/"dx" = "y"/"x"` then m = ?


If y = `("x" + sqrt("x"^2 - 1))^"m"`, then `("x"^2 - 1) "dy"/"dx"` = ______.


If `"x"^7*"y"^9 = ("x + y")^16`, then show that `"dy"/"dx" = "y"/"x"`


If `"x"^"a"*"y"^"b" = ("x + y")^("a + b")`, then show that `"dy"/"dx" = "y"/"x"`


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


y = `e^(x3)`


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


Find `dy/dx if, x= e^(3t), y = e^sqrtt`


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


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


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


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


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×