English

`(sec^2 theta -1)(cosec^2 theta - 1)=1`

Advertisements
Advertisements

Question

`(sec^2 theta -1)(cosec^2 theta - 1)=1`

Advertisements

Solution

LHS = `(sec^2 theta -1)(cosec^2 theta-1)`

       =`tan^2 theta xx cot^2 theta  ( ∵ sec^2 theta - tan^2 theta = 1 and cosec^2 theta - cot^2 theta =1)`

      =` tan^2 theta xx1/(cos^2theta)`

     =1

      =RHS

shaalaa.com
  Is there an error in this question or solution?
Chapter 13: Trigonometric identities - Exercises 1

APPEARS IN

R.S. Aggarwal Mathematics [English] Class 10
Chapter 13 Trigonometric identities
Exercises 1 | Q 2.2

RELATED QUESTIONS

Prove the following trigonometric identities.

`(1 + tan^2 A) + (1 + 1/tan^2 A) = 1/(sin^2 A - sin^4 A)`


Prove the following trigonometric identities.

(cosec θ − sec θ) (cot θ − tan θ) = (cosec θ + sec θ) ( sec θ cosec θ − 2)


Prove the following trigonometric identities.

(sec A − cosec A) (1 + tan A + cot A) = tan A sec A − cot A cosec A


if `x/a cos theta + y/b sin theta = 1` and `x/a sin theta - y/b cos theta = 1` prove that `x^2/a^2 + y^2/b^2  = 2`


Prove the following identities:

`(cotA - cosecA)^2 = (1 - cosA)/(1 + cosA)`


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


If `(cosec theta - sin theta )= a^3 and (sec theta - cos theta ) = b^3 , " prove that " a^2 b^2 ( a^2+ b^2 ) =1`


Write the value of `(1+ tan^2 theta ) ( 1+ sin theta ) ( 1- sin theta)`


Write the value of `3 cot^2 theta - 3 cosec^2 theta.`


Prove the following identity : 

`sqrt((1 + sinq)/(1 - sinq)) + sqrt((1- sinq)/(1 + sinq))` = 2secq


Prove the following identity : 

`1/(cosA + sinA - 1) + 2/(cosA + sinA + 1) = cosecA + secA`


Prove the following identity : 

`[1/((sec^2θ - cos^2θ)) + 1/((cosec^2θ - sin^2θ))](sin^2θcos^2θ) = (1 - sin^2θcos^2θ)/(2 + sin^2θcos^2θ)`


Without using trigonometric table , evaluate : 

`sin72^circ/cos18^circ  - sec32^circ/(cosec58^circ)`


Prove that sin( 90° - θ ) sin θ cot θ = cos2θ.


Prove that `( tan A + sec A - 1)/(tan A - sec A + 1) = (1 + sin A)/cos A`.


Prove that `(tan^2 theta - 1)/(tan^2 theta + 1)` = 1 – 2 cos2θ


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


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


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


Factorize: sin3θ + cos3θ

Hence, prove the following identity:

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


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×