मराठी

Prove That: 1 Cos ( X − a ) Cos ( a − B ) = Tan ( X − B ) − Tan ( X − a ) Sin ( a − B ) - Mathematics

Advertisements
Advertisements

प्रश्न

Prove that:

\[\frac{1}{\cos \left( x - a \right) \cos \left( a - b \right)} = \frac{\tan \left( x - b \right) - \tan \left( x - a \right)}{\sin \left( a - b \right)}\]

 

थोडक्यात उत्तर
Advertisements

उत्तर

\[\text{ RHS }= \frac{\tan(x - b) - \tan(x - a)}{\sin(a - b)}\]
\[ = \frac{\frac{\sin(x - b)}{\cos(x - b)} - \frac{\sin(x - a)}{\cos(x - a)}}{\sin(a - b)}\]
\[ = \frac{\sin(x - b) \cos(x - a) - \sin(x - a) \cos(x - b)}{\sin(a - b) \cos(x - a) \cos(x - b)}\]
\[ = \frac{\sin(x - b - x + a)}{\sin(a - b) \cos(x - a) \cos(x - b)} ( \text{ Using }\sin(A - B) = \sin A\cos B - \cos A\sin B)\]
\[ = \frac{\sin(a - b)}{\sin(a - b) \cos(x - a) \cos(x - b)}\]
\[ = \frac{1}{\cos(x - a) \cos(x - b)} \]
 = LHS
Hence proved.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 7: Values of Trigonometric function at sum or difference of angles - Exercise 7.1 [पृष्ठ २१]

APPEARS IN

आरडी शर्मा Mathematics [English] Class 11
पाठ 7 Values of Trigonometric function at sum or difference of angles
Exercise 7.1 | Q 29.3 | पृष्ठ २१

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

Prove that: `2 sin^2  (3pi)/4 + 2 cos^2  pi/4  + 2 sec^2  pi/3 = 10`


Prove the following:

cos2 2x – cos2 6x = sin 4x sin 8x


Prove the following:

`(sin x + sin 3x)/(cos x + cos 3x) = tan 2x`


Prove the following:

`tan 4x = (4tan x(1 - tan^2 x))/(1 - 6tan^2 x + tan^4 x)`


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 \[\sin A = \frac{4}{5}\] and \[\cos B = \frac{5}{13}\], where 0 < A, \[B < \frac{\pi}{2}\], find the value of the following:

cos (A + B)


 If \[\sin A = \frac{12}{13}\text{ and } \sin B = \frac{4}{5}\], where \[\frac{\pi}{2}\] < A < π and 0 < B < \[\frac{\pi}{2}\], find the following:
cos (A + B)


Prove that:

\[\frac{\sin \left( A - B \right)}{\sin A \sin B} + \frac{\sin \left( B - C \right)}{\sin B \sin C} + \frac{\sin \left( C - A \right)}{\sin C \sin A} = 0\]

 


Prove that:
sin2 B = sin2 A + sin2 (A − B) − 2 sin A cos B sin (A − B)


If tan (A + B) = x and tan (A − B) = y, find the values of tan 2A and tan 2B.

 

If tan A + tan B = a and cot A + cot B = b, prove that cot (A + B) \[\frac{1}{a} - \frac{1}{b}\].


If α, β are two different values of x lying between 0 and 2π, which satisfy the equation 6 cos x + 8 sin x = 9, find the value of sin (α + β).

 

Prove that:

\[\frac{1}{\sin \left( x - a \right) \cos \left( x - b \right)} = \frac{\cot \left( x - a \right) + \tan \left( x - b \right)}{\cos \left( a - b \right)}\]

 


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: 

\[5 \cos x + 3 \sin \left( \frac{\pi}{6} - x \right) + 4\]


Reduce each of the following expressions to the sine and cosine of a single expression: 

\[\sqrt{3} \sin x - \cos x\] 


If 12 sin x − 9sin2 x attains its maximum value at x = α, then write the value of sin α.


If tan (A + B) = p and tan (A − B) = q, then write the value of tan 2B


If A + B + C = π, then \[\frac{\tan A + \tan B + \tan C}{\tan A \tan B \tan C}\] is equal to

 

If cot (α + β) = 0, sin (α + 2β) is equal to


If sin (π cos x) = cos (π sin x), then sin 2x = ______.


The value of cos (36° − A) cos (36° + A) + cos (54° + A) cos (54° − A) is


If tan (π/4 + x) + tan (π/4 − x) = a, then tan2 (π/4 + x) + tan2 (π/4 − x) =


If A − B = π/4, then (1 + tan A) (1 − tan B) is equal to 


The maximum value of \[\sin^2 \left( \frac{2\pi}{3} + x \right) + \sin^2 \left( \frac{2\pi}{3} - x \right)\] is


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


If tanθ = `(sinalpha - cosalpha)/(sinalpha + cosalpha)`, then show that sinα + cosα = `sqrt(2)` cosθ.

[Hint: Express tanθ = `tan (alpha - pi/4) theta = alpha - pi/4`]


If sinθ + cosecθ = 2, then sin2θ + cosec2θ is equal to ______.


If f(x) = cos2x + sec2x, then ______.

[Hint: A.M ≥ G.M.]


If tan θ = 3 and θ lies in third quadrant, then the value of sin θ  ______.


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


The value of `cot(pi/4 + theta)cot(pi/4 - theta)` is ______.


If tanA = `1/2`, tanB = `1/3`, then tan(2A + B) is equal to ______.


If sinθ + cosθ = 1, then the value of sin2θ is equal to ______.


If tanα = `1/7`, tanβ = `1/3`, then cos2α is equal to ______.


If sinx + cosx = a, then |sinx – cosx| = ______.


3(sinx – cosx)4 + 6(sinx + cosx)2 + 4(sin6x + cos6x) = ______.


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

If tanθ + tan2θ + `sqrt(3)` tanθ tan2θ = `sqrt(3)`, then θ = `("n"pi)/3 + pi/9`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×