हिंदी

Find the principal solution of the following equation: cosθ = 12 - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

Find the principal solution of the following equation: 

cosθ = `(1)/(2)`

योग
Advertisements

उत्तर

We know that, `cos  pi/(3) = 1/2` and cos(2π - θ) = cosθ

`∴ cos  π/3 = cos(2pi - pi/3) = cos  (5pi)/3`

`∴ cos  pi/3 = cos  (5pi)/3 = 1/2`, where

`0 < pi/3 < 2pi and  0 < (5pi)/3 < 2pi`

`∴ cosθ = 1/2 "gives" cosθ = cos  pi/(3) = cos  (5pi)/(3)`

∴ θ = `pi/(3) and θ = (5pi)/(3)`

Hence, the required principal solutions are

`θ = pi/(3) and θ = (5pi)/(3)`.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 3: Trigonometric Functions - Exercise 3.1 [पृष्ठ ७५]

APPEARS IN

बालभारती Mathematics and Statistics 1 (Arts and Science) [English] Standard 12 Maharashtra State Board
अध्याय 3 Trigonometric Functions
Exercise 3.1 | Q 1.1 | पृष्ठ ७५

संबंधित प्रश्न

Find the principal solution of the following equation:

cot θ = 0


Find the principal solution of the following equation:

sin θ = `-1/2`


Find the general solution of the following equation :

cosθ = `sqrt(3)/(2)`


Find the general solution of the following equation:

sin 2θ = `1/2`


Find the general solution of the following equation:

tan `(2θ)/(3) = sqrt3`


Find the general solution of the following equation: 

tan3θ = 3 tanθ.


Find the general solution of the following equation:

cosθ + sinθ = 1.


State whether the following equation have solution or not?

cos 2θ = – 1


State whether the following equation have solution or not?

3 tanθ = 5


In Δ ABC, prove that a3 sin(B – C) + b3sin(C – A) + c3sin(A – B) = 0


In ΔABC, if a cos A = b cos B then prove that the triangle is either a right angled or an isosceles traingle.


Select the correct option from the given alternatives:

The value of cot (tan-12x + cot-12x) is


If `"sin"^-1 4/5 + "cos"^-1 12/13 = "sin"^-1 alpha`, then α = ______.


Select the correct option from the given alternatives:

`"tan"(2"tan"^-1 (1/5) - pi/4)` = ______


Select the correct option from the given alternatives:

In any ΔABC, if acos B = bcos A, then the triangle is


Find the principal solutions of the following equation:

sin 2θ = `-1/2`


Find the principal solutions of the following equation:

tan 3θ = - 1


Find the general solutions of the following equation:

`tan theta = - sqrt3`


Find the general solutions of the following equation:

`tan^2 theta = 3`


If sin-1(1 - x) - 2 sin-1x =  `pi/2`, then find the value of x.


If tan-12x + tan-13x = `pi/4`, then find the value of x.


Show that `tan^-1  1/2 - tan^-1  1/4 = tan^-1  2/9`.


Show that `2 cot^(-1)  3/2 +  sec^(-1)  13/12 = π/2`


Prove the following:

`cos^-1 "x" = tan^-1 (sqrt(1 - "x"^2)/"x")`, if x > 0


Prove the following:

`cos^-1 "x" = pi + tan^-1 (sqrt(1 - "x"^2)/"x")`, if x < 0


If x, y, z are positive, then prove that

`tan^-1 (("x - y")/(1 + "xy")) + tan^-1 (("y - z")/(1 + "yz")) + tan^-1 (("z - x")/(1 + "zx")) = 0`


If cos-1 x + cos-1y + cos-1z = 3π, then show that x2 + y2 + z2 + 2xyz = 1.


Find the principal solutions of sin x = `-1/2`


If cos–1x + cos–1y – cos–1z = 0, then show that x2 + y2 + z2 – 2xyz = 1


If `|bar"a"|` = 10, `|bar"b"| = 2`, then `sqrt(|bar"a" xx bar"b"|^2 + |bar"a"*bar"b"|^2)` = ?


If x + y = `pi/2`, then the maximum value of sin x. sin y is.


Which of the following equations has no solution?


The value of `tan^-1  1/3 + tan^-1  1/5 + tan^-1  1/7 + tan^-1  1/8` is ______.


The number of solutions of cos 2θ = sin θ in (0, 2π) is ______


If function

f(x) = `x - |x|/x, x < 0`
      = `x + |x|/x, x > 0`
      = 1, x = 0, then


The value of θ in (π, 2π) satisfying the equation sin2θ - cos2θ = 1 is ______ 


The measure of the angle between lines (sin2θ - 1)x2 - 2xy cos2θ + cos2θy2 = 0 is ______ 


If `(tan 3 theta - 1)/(tan 3 theta + 1) = sqrt3`, then the general value of θ is ______.


The equation 3sin2x + 10 cos x – 6 = 0 is satisfied, if ______.


If y = `(2sinα)/(1 + cosα + sinα)`, then value of `(1 - cos α + sin α)/(1 + sin α)` is ______.


Which of the following equation has no solution?


The number of principal solutions of tan 2θ = 1 is ______.


Prove that the general solution of cos θ = cos α is θ = 2nπ ± α, n ∈ Z.


If `2sin^-1  3/7` = cos–1β, then find the value of β.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×