मराठी

Prove the following: cos(π+x)cos(-x)sin(π-x)cos(π2+x)= cot2x - Mathematics

Advertisements
Advertisements

प्रश्न

Prove the following:

`(cos (pi + x) cos (-x))/(sin(pi - x) cos (pi/2 + x)) =  cot^2 x`

बेरीज
Advertisements

उत्तर

L.H.S. = `(cos (pi + x) cos (-x))/(sin(pi - x) cos (pi/2 + x))`

Now using `sin (π - x) = sin x, cos (pi/2+x) = - sin x`

L.H.S. = `(- cosx xx cosx )/(sinx  (-  sinxx)`

= `cos^2x/sin^2x = (cosx/sinx)^2`

= `cot^2xx`

= R.H.S.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 3: Trigonometric Functions - Exercise 3.3 [पृष्ठ ७३]

APPEARS IN

एनसीईआरटी Mathematics [English] Class 11
पाठ 3 Trigonometric Functions
Exercise 3.3 | Q 8 | पृष्ठ ७३

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

Prove that  `cot^2  pi/6 + cosec  (5pi)/6 + 3 tan^2  pi/6 = 6`


Prove the following: `cos (pi/4 xx x) cos (pi/4 - y) - sin (pi/4 -  x)sin (pi/4  - y) =  sin (x + y)`


Prove the following:

`cos ((3pi)/4 + x) - cos((3pi)/4 - x) = -sqrt2 sin x`


Prove the following:

cos2 2x – cos2 6x = sin 4x sin 8x


Prove the following:

`(cos9x - cos5x)/(sin17x - sin 3x) = - (sin2x)/(cos 10x)`


Prove that: `(cos x - cosy)^2 + (sin x - sin y)^2 = 4 sin^2  (x - y)/2`


Prove that: sin x + sin 3x + sin 5x + sin 7x = 4 cos x cos 2x sin 4x


If \[\cos A = - \frac{12}{13}\text{ and }\cot B = \frac{24}{7}\], where A lies in the second quadrant and B in the third quadrant, find the values of the following:
sin (A + B)


If \[\cos A = - \frac{12}{13}\text{ and }\cot B = \frac{24}{7}\], where A lies in the second quadrant and B in the third quadrant, find the values of the following:
cos (A + B)


Prove that
\[\frac{\tan A + \tan B}{\tan A - \tan B} = \frac{\sin \left( A + B \right)}{\sin \left( A - B \right)}\]


Prove that

\[\frac{\cos 9^\circ + \sin 9^\circ}{\cos 9^\circ - \sin 9^\circ} = \tan 54^\circ\]

Prove that:

\[\sin\left( \frac{\pi}{3} - x \right)\cos\left( \frac{\pi}{6} + x \right) + \cos\left( \frac{\pi}{3} - x \right)\sin\left( \frac{\pi}{6} + x \right) = 1\]

 


Prove that:
sin2 (n + 1) A − sin2 nA = sin (2n + 1) A sin A.


Prove that: \[\frac{\sin \left( A + B \right) + \sin \left( A - B \right)}{\cos \left( A + B \right) + \cos \left( A - B \right)} = \tan A\]


Prove that:
\[\frac{\tan \left( A + B \right)}{\cot \left( A - B \right)} = \frac{\tan^2 A - \tan^2 B}{1 - \tan^2 A \tan^2 B}\]


If tan A = x tan B, prove that
\[\frac{\sin \left( A - B \right)}{\sin \left( A + B \right)} = \frac{x - 1}{x + 1}\]


If sin α + sin β = a and cos α + cos β = b, show that

\[\sin \left( \alpha + \beta \right) = \frac{2ab}{a^2 + b^2}\]

 


If angle \[\theta\]  is divided into two parts such that the tangents of one part is \[\lambda\] times the tangent of other, and \[\phi\] is their difference, then show that\[\sin\theta = \frac{\lambda + 1}{\lambda - 1}\sin\phi\]

 

Find the maximum and minimum values of each of the following trigonometrical expression: 

12 cos x + 5 sin x + 4 


Find the maximum and minimum values of each of the following trigonometrical expression:

sin x − cos x + 1


Write the maximum and minimum values of 3 cos x + 4 sin x + 5. 


If \[\frac{\cos \left( x - y \right)}{\cos \left( x + y \right)} = \frac{m}{n}\]  then write the value of tan x tan y


The value of \[\sin^2 \frac{5\pi}{12} - \sin^2 \frac{\pi}{12}\] 


If \[\tan A = \frac{a}{a + 1}\text{ and } \tan B = \frac{1}{2a + 1}\] 


tan 3A − tan 2A − tan A =


If \[\cos P = \frac{1}{7}\text{ and }\cos Q = \frac{13}{14}\], where P and Q both are acute angles. Then, the value of P − Q is

 


If \[\tan\theta = \frac{1}{2}\] and \[\tan\phi = \frac{1}{3}\], then the value of \[\tan\phi = \frac{1}{3}\] is 

 

 


If \[\tan\alpha = \frac{x}{x + 1}\] and \[\tan\alpha = \frac{x}{x + 1}\], then \[\alpha + \beta\] is equal to


If `(sin(x + y))/(sin(x - y)) = (a + b)/(a - b)`, then show that `tanx/tany = a/b` [Hint: Use Componendo and Dividendo].


If cotθ + tanθ = 2cosecθ, then find the general value of θ.


Find the general solution of the equation `(sqrt(3) - 1) costheta + (sqrt(3) + 1) sin theta` = 2

[Hint: Put `sqrt(3) - 1` = r sinα, `sqrt(3) + 1` = r cosα which gives tanα = `tan(pi/4 - pi/6)` α = `pi/12`]


If tanα = `m/(m +  1)`, tanβ = `1/(2m + 1)`, then α + β is equal to ______.


The value of sin(45° + θ) - cos(45° - θ) is ______.


If α + β = `pi/4`, then the value of (1 + tan α)(1 + tan β) is ______.


State whether the statement is True or False? Also give justification.

If cosecx = 1 + cotx then x = 2nπ, 2nπ + `pi/2`


State whether the statement is True or False? Also give justification.

If tan(π cosθ) = cot(π sinθ), then `cos(theta - pi/4) = +- 1/(2sqrt(2))`.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×