हिंदी

If tan θ – sin^2θ = cos^2θ, then show that sin^2θ = 1/2.

Advertisements
Advertisements

प्रश्न

If tan θ – sin2θ = cos2θ, then show that `sin^2θ = 1/2`.

योग
Advertisements

उत्तर

tan θ – sin2θ = cos2θ   ...[Given]

∴ tan θ = sin2θ + cos2θ

∴ tan θ = 1   ...[∵ sin2θ + cos2θ = 1]

But, tan 45° = 1

∴ tan θ = tan 45°

∴ θ = 45°

sin2θ = sin245°

= `(1/sqrt(2))^2`

= `1/2`

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

संबंधित प्रश्न

Prove that `(sin theta)/(1-cottheta) + (cos theta)/(1 - tan theta) = cos theta + sin theta`


Prove the following trigonometric identities.

sec6 θ = tan6 θ + 3 tan2 θ sec2 θ + 1


Prove the following trigonometric identities.

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


Prove the following trigonometric identities.

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


Prove the following identities:

`tan A - cot A = (1 - 2cos^2A)/(sin A cos A)`


Prove the following identities:

(cos A + sin A)2 + (cos A – sin A)2 = 2


Prove the following identities:

`1/(cosA + sinA) + 1/(cosA - sinA) = (2cosA)/(2cos^2A - 1)`


`sin theta (1+ tan theta) + cos theta (1+ cot theta) = ( sectheta+ cosec  theta)`


Prove the following identities:

`sin theta/((cot theta + "cosec"  theta)) - sin theta/((cot theta - "cosec"  theta)) = 2`


Prove the following identities:

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


Write the value of `(cot^2 theta -  1/(sin^2 theta))`. 


If `sec theta + tan theta = x,"  find the value of " sec theta`


What is the value of 9cot2 θ − 9cosec2 θ? 


If cos  \[9\theta\] = sin \[\theta\] and  \[9\theta\]  < 900 , then the value of tan \[6 \theta\] is


Prove the following identity : 

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


Prove that :(sinθ+cosecθ)2+(cosθ+ secθ)2 = 7 + tan2 θ+cotθ.


Prove that `cos θ/sin(90° - θ) + sin θ/cos (90° - θ) = 2`.


If A + B = 90°, show that `(sin B + cos A)/sin A = 2tan B + tan A.`


Prove the following identities:
`1/(sin θ + cos θ) + 1/(sin θ - cos θ) = (2sin θ)/(1 - 2 cos^2 θ)`.


If sin θ + cos θ = p and sec θ + cosec θ = q, then prove that q(p2 – 1) = 2p.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×