हिंदी

Prove that (tan(90 – θ) + cot(90 – θ))/(cosec θ) = sec θ.

Advertisements
Advertisements

प्रश्न

Prove that `(tan(90 - θ) + cot(90 - θ))/("cosec"  θ) = sec θ`.

प्रमेय
Advertisements

उत्तर

L.H.S. = `(tan(90 - θ) + cot(90 - θ))/("cosec"  θ)`

= `1/("cosec"  θ)(cot θ + tan θ)`   ...`[(∵ tan(90 - θ) = cot θ),(cot(90 - θ) = tan θ)]`

= sin θ (cot θ + tan θ)

= `sin θ ((cos θ)/(sin θ) + (sin θ)/(cos θ))`

= `sin θ ((cos^2θ + sin^2θ)/(sinθ cosθ))`

= `sin θ (1/(sin θ cos θ))`   ...[∵ sin2θ + cos2θ = 1]

= `1/(cos θ)`

= sec θ

= R.H.S.

∴ `(tan(90 - θ) + cot(90 - θ))/("cosec"  θ) = sec θ`

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 6: Trigonometry - Exercise

संबंधित प्रश्न

If tanθ + sinθ = m and tanθ – sinθ = n, show that `m^2 – n^2 = 4\sqrt{mn}.`


Prove that `\frac{\sin \theta -\cos \theta }{\sin \theta +\cos \theta }+\frac{\sin\theta +\cos \theta }{\sin \theta -\cos \theta }=\frac{2}{2\sin^{2}\theta -1}`


Prove that `(tan^2 theta)/(sec theta - 1)^2 = (1 + cos theta)/(1 - cos theta)`


Prove the following trigonometric identity.

`cos^2 A + 1/(1 + cot^2 A) = 1`


Prove the following trigonometric identities

cosec6θ = cot6θ + 3 cot2θ cosec2θ + 1


`(cos^3 θ + sin^3 θ)/(cos θ + sin θ) + (cos ^3 θ - sin^3 θ)/(cos θ - sin θ) = 2`


`(sin theta)/((sec theta + tan theta -1)) + cos theta/((cosec theta + cot theta -1))=1`


Prove the following identities:

`(1 + tan theta + cot theta)(sin theta - cos theta) = ((sec theta)/("cosec"^2 theta) - ("cosec"  theta)/(sec^2 theta))`


Write the value of ` sin^2 theta cos^2 theta (1+ tan^2 theta ) (1+ cot^2 theta).`


If `cos theta = 2/3 , "write the value of" ((sec theta -1))/((sec theta +1))`


If 3 `cot theta = 4 , "write the value of" ((2 cos theta - sin theta))/(( 4 cos theta - sin theta))`


Write True' or False' and justify your answer the following: 

\[ \cos \theta = \frac{a^2 + b^2}{2ab}\]where a and b are two distinct numbers such that ab > 0.


The value of sin2 29° + sin2 61° is


If  cos (\[\alpha + \beta\]= 0 , then sin \[\left( \alpha - \beta \right)\] can be reduced to  

 


Prove the following identity :

`sec^2A.cosec^2A = tan^2A + cot^2A + 2`


Prove that cosec2 (90° - θ) + cot2 (90° - θ) = 1 + 2 tan2 θ.


If x sin3 θ + y cos3 θ = sin θ cos θ and x sin θ = y cos θ, then prove that x2 + y2 = 1


Prove that sin θ (1 – tan θ) – cos θ (1 – cot θ) = cosec θ – sec θ.


Eliminate θ if x = r cosθ and y = r sinθ.


(1 + sin A)(1 – sin A) is equal to ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×