मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता ११ वी

Prove the following identities: 1 + 3cosec2θ cot2θ + cot6θ = cosec6θ

Advertisements
Advertisements

प्रश्न

Prove the following identity:

1 + 3cosec2θ cot2θ + cot6θ = cosec6θ

बेरीज
Advertisements

उत्तर

L.H.S. = 1 + 3cosec2θ cot2θ + cot6θ

 = 1 + 3 cosec2θ cot2θ + (cot2θ)3

= 1 + 3 cosec2θ (cosec2θ – 1) + (cosec2θ – 1)   ...`[(1 + cot^2theta = cosec^2theta),(cot^2theta = cosec^2 theta - 1)]`

= 1 + 3 cosec4θ – 3 cosec2θ + cosec6θ – 3 cosec4θ + 3cosec2θ – 1       ...[(a - b)3 = a3 - 3a2b + 3ab2 - b3]

= `cancel(1) + cancel(3 cosec^4θ) - cancel(3 cosec^2θ)  +  cosec^6θ - cancel(3 cosec^4 θ) + cancel(3cosec^2 θ) cancel(- 1)` 

= cosec6θ

= R.H.S.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 2: Trigonometry - 1 - EXERCISE 2.2 [पृष्ठ ३१]

APPEARS IN

संबंधित प्रश्‍न

Evaluate the following : 

sin 30° × cos 45° × tan 360°


If tanθ = `1/2`, evaluate `(2sin theta + 3cos theta)/(4cos theta + 3sin theta)`


Eliminate θ from the following :

x = 4cosθ − 5sinθ, y = 4sinθ + 5cosθ


Eliminate θ from the following:

2x = 3 − 4 tan θ, 3y = 5 + 3 sec θ


Find the acute angle θ such that 2 cos2θ = 3 sin θ.


Find sinθ such that 3cosθ + 4sinθ = 4


If cotθ = `3/4` and π < θ < `(3pi)/2` then find the value of 4cosecθ + 5cosθ.


Prove the following identities: 

(cos2A – 1) (cot2A + 1) = −1


Prove the following identities:

(sinθ + sec θ)2 + (cosθ + cosec θ)2 = (1 + cosecθ sec θ)2 


Prove the following identities:

(1 + cot θ – cosec θ)(1 + tan θ + sec θ) = 2


Prove the following identities:

`sintheta/(1 + costheta) + (1 + costheta)/sintheta` = 2cosecθ


Prove the following identity:

`tantheta/(sectheta - 1) = (sectheta + 1)/tantheta`


Select the correct option from the given alternatives: 

`tan"A"/(1 + sec"A") + (1 + sec"A")/tan"A"` is equal to


Select the correct option from the given alternatives:

If θ = 60°, then `(1 + tan^2theta)/(2tantheta)` is equal to


Select the correct option from the given alternatives:

If cosecθ − cotθ = q, then the value of cot θ is


Select the correct option from the given alternatives:

The value of tan1°.tan2°tan3°..... tan89° is equal to


Prove the following:  

sin2A cos2B + cos2A sin2B + cos2A cos2B + sin2A sin2B = 1


Prove the following:

`((1 + cot theta + tan theta)(sin theta - costheta)) /(sec^3theta - "cosec"^3theta)`= sin2θ cos2θ


Prove the following:

2 sec2θ – sec4θ – 2cosec2θ + cosec4θ = cot4θ – tan4θ


Prove the following:

sin4θ + cos4θ = 1 – 2 sin2θ cos2θ


Prove the following:

2(sin6θ + cos6θ) – 3(sin4θ + cos4θ) + 1 = 0


Prove the following:

sin4θ +2sin2θ . cos2θ = 1 − cos4θ


Prove the following:

`(sin^3theta + cos^3theta)/(sintheta + costheta) + (sin^3theta - cos^3theta)/(sintheta - costheta)` = 2


Prove the following:

sin6A + cos6A = 1 − 3sin2A + 3 sin4A


Prove the following:

(1 + tanA · tanB)2 + (tanA − tanB)2 = sec2A · sec2B


Prove the following:

`(1 + cottheta  +  "cosec" theta)/(1 - cottheta  +  "cosec" theta) = ("cosec" theta  + cottheta - 1)/(cottheta - "cosec"theta + 1)`


Prove the following:

`(tantheta + sectheta - 1)/(tantheta + sectheta + 1) = tantheta/(sec theta + 1)`


Prove the following:

`("cosec"theta + cottheta - 1)/( "cosec"theta + cot theta + 1) =(1-sintheta)/costheta`


If θ lies in the first quadrant and 5 tan θ = 4, then `(5 sin θ - 3 cos θ)/(sin θ + 2 cos θ)` is equal to ______.


If 5 tan θ = 4. then `(5 sin θ − 3 cos θ)/(5 sin θ + 2 cos θ)` = ______. 


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×