हिंदी

If x = 3sint – sin 3t, y = 3cost – cos 3t, find dydxdydx at t = π3 - Mathematics

Advertisements
Advertisements

प्रश्न

If x = 3sint – sin 3t, y = 3cost – cos 3t, find `"dy"/"dx"` at t = `pi/3`

योग
Advertisements

उत्तर

Given that: x = 3sint – sin 3t, y = 3cost – cos 3t.

Differentiating both parametric functions w.r.t. t

`"dx"/"dt" = 3 cos "t" - cos 3"t" * 3`

= 3(cos t – cos 3t)

`"dy"/"dx" = -3 sin "t" + sin 3"t" * 3`

= 3(– sin t + sin 3t)

∴ `"dy"/"dx" = ("dy"/"dt")/("dx"/"dt")`

= `(3(- sin "t" + sin 3"t"))/(3(cos "t" - cos 3"t"))`

= `(-sin "t" + sin 3"t")/(cos "t" - cos 3"t")`

Put t = `pi/3`

`"dy"/"dx" = (- sin  pi/3 + sin 3 (pi/3))/(cos  pi/3 - cos  3 (pi/3))`

= `(- sqrt(3)/2 + sin pi)/(1/2 - cos pi)`

= `(- sqrt(3)/2 + 0)/(1/2 - (- 1))`

= `(- sqrt(3)/2)/(1/2 + 1)`

= `(- sqrt(3)/2)/(3/2)`

= `(-1)/sqrt(3)`

Hence, `"dy"/"dx" = (-1)/sqrt(3)`.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 5: Continuity And Differentiability - Exercise [पृष्ठ ११०]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
अध्याय 5 Continuity And Differentiability
Exercise | Q 51 | पृष्ठ ११०

संबंधित प्रश्न

If  `log_10((x^3-y^3)/(x^3+y^3))=2 "then show that"  dy/dx = [-99x^2]/[101y^2]`


find dy/dx if x=e2t , y=`e^sqrtt`


If x = f(t), y = g(t) are differentiable functions of parammeter ‘ t ’ then prove that y is a differentiable function of 'x' and  hence, find dy/dx if x=a cost, y=a sint


If `x=a(t-1/t),y=a(t+1/t)`, then show that `dy/dx=x/y`


If `ax^2+2hxy+by^2=0` , show that `(d^2y)/(dx^2)=0`


If x=α sin 2t (1 + cos 2t) and y=β cos 2t (1cos 2t), show that `dy/dx=β/αtan t`


If x = a sin 2t (1 + cos 2t) and y = b cos 2t (1 – cos 2t) then find `dy/dx `

 


Find the value of `dy/dx " at " theta =pi/4 if x=ae^theta (sintheta-costheta) and y=ae^theta(sintheta+cos theta)`


If x = cos t (3 – 2 cos2 t) and y = sin t (3 – 2 sin2 t), find the value of dx/dy at t =4/π.


Derivatives of  tan3θ with respect to sec3θ at θ=π/3 is

(A)` 3/2`

(B) `sqrt3/2`

(C) `1/2`

(D) `-sqrt3/2`


If x and y are connected parametrically by the equations, without eliminating the parameter, find `bb(dy/dx)`.

x = sin t, y = cos 2t


If x and y are connected parametrically by the equations, without eliminating the parameter, find `bb(dy/dx)`.

x = 4t, y = `4/y`


If x and y are connected parametrically by the equations, without eliminating the parameter, find `bb(dy/dx)`.

x = cos θ – cos 2θ, y = sin θ – sin 2θ


If x and y are connected parametrically by the equations, without eliminating the parameter, find `bb(dy/dx)`.

x = a (θ – sin θ), y = a (1 + cos θ)


If x and y are connected parametrically by the equations, without eliminating the parameter, find `bb(dy/dx)`.

x = `a(cos t + log tan  t/2)`, y = a sin t


If x = `sqrt(a^(sin^(-1)t))`, y = `sqrt(a^(cos^(-1)t))` show that `dy/dx = - y/x`.


If x = a (2θ – sin 2θ) and y = a (1 – cos 2θ), find `dy/dx` when `theta = pi/3`


If X = f(t) and Y = g(t) Are Differentiable Functions of t ,  then prove that y is a differentiable function of x and

`"dy"/"dx" =("dy"/"dt")/("dx"/"dt" ) , "where" "dx"/"dt" ≠ 0`

Hence find `"dy"/"dx"` if x = a cos2 t and y = a sin2 t.


The cost C of producing x articles is given as C = x3-16x2 + 47x.  For what values of x, with the average cost is decreasing'?  


If y = sin -1 `((8x)/(1 + 16x^2))`, find `(dy)/(dx)`


Evaluate : `int  (sec^2 x)/(tan^2 x + 4)` dx


x = `"t" + 1/"t"`, y = `"t" - 1/"t"`


If x = ecos2t and y = esin2t, prove that `"dy"/"dx" = (-y log x)/(xlogy)`


Differentiate `tan^-1 ((sqrt(1 + x^2) - 1)/x)` w.r.t. tan–1x, when x ≠ 0


If x = sint and y = sin pt, prove that `(1 - x^2) ("d"^2"y")/("dx"^2) - x "dy"/"dx" + "p"^2y` = 0


If x = t2, y = t3, then `("d"^2"y")/("dx"^2)` is ______.


Derivative of x2 w.r.t. x3 is ______.


If `"x = a sin"  theta  "and  y = b cos"  theta, "then"  ("d"^2 "y")/"dx"^2` is equal to ____________.


If y `= "Ae"^(5"x") + "Be"^(-5"x") "x"  "then"  ("d"^2 "y")/"dx"^2` is equal to ____________.


Form the point of intersection (P) of lines given by x2 – y2 – 2x + 2y = 0, points A, B, C, Dare taken on the lines at a distance of `2sqrt(2)` units to form a quadrilateral whose area is A1 and the area of the quadrilateral formed by joining the circumcentres of ΔPAB, ΔPBC, ΔPCD, ΔPDA is A2, then `A_1/A_2` equals


Let a function y = f(x) is defined by x = eθsinθ and y = θesinθ, where θ is a real parameter, then value of `lim_(θ→0)`f'(x) is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×