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

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

Advertisements
Advertisements

प्रश्न

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

बेरीज
Advertisements

उत्तर

0 ≤ cos-1x ≤ π and 

cos-1x + cos-1 y + cos-1z = 3π

∴ cos-1x = π, cos-1y = π  and cos-1z = π

∴ x = y = z = cos π = - 1

∴ x2 + y2 + z2 + 2xyz

= (- 1)2 + (- 1)2 + (- 1)2 + 2(- 1)(- 1)(- 1)

= 1 + 1 + 1 - 2

= 3 - 2

= 1.

shaalaa.com
Trigonometric Equations and Their Solutions
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 3: Trigonometric Functions - Miscellaneous exercise 3 [पृष्ठ १११]

APPEARS IN

बालभारती Mathematics and Statistics 1 (Arts and Science) [English] Standard 12 Maharashtra State Board
पाठ 3 Trigonometric Functions
Miscellaneous exercise 3 | Q 39 | पृष्ठ १११

संबंधित प्रश्‍न

Find the principal solution of the following equation: 

Sec θ = `(2)/sqrt(3)`


Find the principal solution of the following equation: 

tan θ = – 1


Find the general solution of the following equation:

sinθ = `1/2`.


Find the general solution of the following equation:

cot θ = 0.


Find the general solution of the following equation:

sec θ = `sqrt(2)`.


Find the general solution of the following equation:

sin 2θ = `1/2`


Find the general solution of the following equation:

4 cos2 θ  = 3


Find the general solution of the following equation:

cos 4θ = cos 2θ


Find the general solution of the following equation:

cosθ + sinθ = 1.


State whether the following equation have solution or not?

3 tanθ = 5


With the usual notations prove that `2{asin^2  "C"/(2) + "c"sin^2  "A"/(2)}` = a – b + c.


Select the correct option from the given alternatives:

In ΔABC if c2 + a2 – b2 = ac, then ∠B = ____.


If in a triangle, the angles are in A.P. and b: c = `sqrt3: sqrt2`, then A is equal to


`"cos"^-1 ("cos" (7pi)/6)` = _________.


Select the correct option from the given alternatives:

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


Select the correct option from the given alternatives:

`2 "tan"^-1 (1/3) + "tan"^-1 (1/7) =` _____


The principal value branch of sec-1x is ______.


`cos[tan^-1  1/3 + tan^-1  1/2]` = ______


If tan θ + tan 2θ + tan 3θ = tan θ.tan 2θ. tan 3θ, then the general value of the θ is ______.


Find the general solutions of the following equation:

`tan theta = - sqrt3`


Find the general solutions of the following equation:

sin θ - cos θ = 1


In Δ ABC, prove that `cos(("A" - "B")/2) = (("a" + "b")/"c")sin  "C"/2` .


With the usual notations, prove that `(sin("A" - "B"))/(sin ("A" + "B")) = ("a"^2 - "b"^2)/"c"^2`


In Δ ABC, if cos A = sin B - cos C then show that it is a right-angled triangle.


State whether the following equation has a solution or not?

3 sin θ = 5


Show that `cot^-1  1/3 - tan^-1  1/3 = cot^-1  3/4`.


Find the principal solutions of cos 2𝑥 = 1


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


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


The general solution of sec θ = `sqrt2` is


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


If y = sin-1 `[(sqrt(1 + x) + sqrt(1 - x))/2]`, then `"dy"/"dx"` = ?


The values of x in `(0, pi/2)` satisfying the equation sin x cos x = `1/4` are ______.


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


The general value of θ in the equation `2sqrt(3) cos theta = tan theta` is ______.


The general solution of cosec x = `-sqrt2` is ______ 


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


The general solution of the equation tan θ + tan 4θ + tan 7θ = tan θ tan 4θ tan 7θ is ______.


General solution of the equation sin 2x – sin 4x + sin 6x = 0 is ______.


The general solution to cos100x – sin100x = 1 is ______.


If `sin^-1  4/5 + cos^-1  12/13` = sin–1α, then find the value of α.


If tan θ + sec θ = `sqrt(3)`, find the general value of θ.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×