рдорд░рд╛рдареА

`(Tan a + Tanb )/(Cot a + Cot B) = Tan a Tan B`

Advertisements
Advertisements

рдкреНрд░рд╢реНрди

`(tan A + tanB )/(cot A + cot B) = tan A tan B`

Advertisements

рдЙрддреНрддрд░

LHS = `(tan A + tanB )/(cot A + cot B) `

       =`(tan A + tan B)/(1/ tan A + 1/ tanB)`

       =` (tan A + tan B)/( (tan A+tan B)/ (tan A tan B)`

        =`(tan A tan B ( tan A + tan B))/((tan A + tan B ))`

        = ЁЭСбЁЭСОЁЭСЫЁЭР┤ ЁЭСбЁЭСОЁЭСЫЁЭР╡
        = RHS
Hence, LHS = RHS

shaalaa.com
  рдпрд╛ рдкреНрд░рд╢реНрдирд╛рдд рдХрд┐рдВрд╡рд╛ рдЙрддреНрддрд░рд╛рдд рдХрд╛рд╣реА рддреНрд░реБрдЯреА рдЖрд╣реЗ рдХрд╛?
рдкрд╛рда 13: Trigonometric identities - Exercises 1

APPEARS IN

рд╕рдВрдмрдВрдзрд┐рдд рдкреНрд░рд╢реНтАНрди

Prove the following trigonometric identities.

`1/(1 + sin A) + 1/(1 - sin A) =  2sec^2 A`


Prove the following trigonometric identities.

`(cot A - cos A)/(cot A + cos A) = (cosec A - 1)/(cosec A + 1)`


Prove that:

(sec A − tan A)2 (1 + sin A) = (1 − sin A)


Show that : `sinAcosA - (sinAcos(90^circ - A)cosA)/sec(90^circ - A) - (cosAsin(90^circ - A)sinA)/(cosec(90^circ - A)) = 0`


`(sin theta +cos theta )/(sin theta - cos theta)+(sin theta- cos theta)/(sin theta + cos theta) = 2/((sin^2 theta - cos ^2 theta)) = 2/((2 sin^2 theta -1))`


`((sin A-  sin B ))/(( cos A + cos B ))+ (( cos A - cos B ))/(( sinA + sin B ))=0` 


If `(cot theta ) = m and ( sec theta - cos theta) = n " prove that " (m^2 n)(2/3) - (mn^2)(2/3)=1`


Define an identity.


If sin2 θ cos2 θ (1 + tan2 θ) (1 + cot2 θ) = λ, then find the value of λ. 


If x = a sec θ cos ╧Х, y = b sec θ sin ╧Х and z = c tan θ, then\[\frac{x^2}{a^2} + \frac{y^2}{b^2}\]


Prove the following identity :

`sinθ(1 + tanθ) + cosθ(1 +cotθ) = secθ + cosecθ` 


For ΔABC , prove that : 

`tan ((B + C)/2) = cot "A/2`


Find the value of sin 30° + cos 60°.


If sec θ = `25/7`, then find the value of tan θ.


Prove that `(sin 70°)/(cos 20°) + (cosec 20°)/(sec 70°) - 2 cos 70° xx cosec 20°` = 0.


cot θ . tan θ = ?


(sec θ + tan θ) . (sec θ – tan θ) = ?


Prove that `sqrt((1 + cos A)/(1 - cos A)) = "cosec"  A + cot A`.


Prove the following that:

`tan^3θ/(1 + tan^2θ) + cot^3θ/(1 + cot^2θ)` = secθ cosecθ – 2 sinθ cosθ


Factorize: sin3θ + cos3θ

Hence, prove the following identity:

`(sin^3θ + cos^3θ)/(sin θ + cos θ) + sin θ cos θ = 1`


Share
Notifications

Englishрд╣рд┐рдВрджреАрдорд░рд╛рдареА


      Forgot password?
Use app×