हिंदी

Prove the following trigonometric identities. (1 - sin θ)/(1 + sin θ) = (sec θ - tan θ)^2

Advertisements
Advertisements

प्रश्न

Prove the following trigonometric identities.

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

Prove that:

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

प्रमेय
Advertisements

उत्तर

We have to prove  `(1 - sin θ)/(1 + sin θ) = (sec θ - tan θ)^2`

We know that, sin2 θ + cos2 θ = 1

Multiplying both numerator and denominator by  (1 − sin θ), we have

`(1 - sin θ)/(1 + sin θ) = ((1 - sin θ)(1 -  sin θ))/((1 + sin θ)(1 - sin θ))`

`= (1 - sin θ)^2/(1 - sin^2 θ)`

`= ((1 - sin θ)/cos θ)^2`

`= (1/cos θ - sin θ/cos θ)^2`

`= (sec θ - tan θ)^2`

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 18: Trigonometric identities - CHAPTER TEST [पृष्ठ ४२७]

APPEARS IN

नूतन Mathematics [English] Class 10 ICSE
अध्याय 18 Trigonometric identities
CHAPTER TEST | Q 5. | पृष्ठ ४२७
आर.डी. शर्मा Mathematics [English] Class 10
अध्याय 11 Trigonometric Identities
Exercise 11.1 | Q 14 | पृष्ठ ४४

संबंधित प्रश्न

If acosθ – bsinθ = c, prove that asinθ + bcosθ = `\pm \sqrt{a^{2}+b^{2}-c^{2}`


Prove the following identities, where the angles involved are acute angles for which the expressions are defined:

`(cos A-sinA+1)/(cosA+sinA-1)=cosecA+cotA ` using the identity cosec2 A = 1 cot2 A.


if `cos theta = 5/13` where `theta` is an acute angle. Find the value of `sin theta`


Prove the following trigonometric identities.

`((1 + tan^2 theta)cot theta)/(cosec^2 theta)   = tan theta`


Prove the following trigonometric identities

sec4 A(1 − sin4 A) − 2 tan2 A = 1


Prove the following identities:

(cosec A + sin A) (cosec A – sin A) = cot2 A + cos2 A


Prove the following identities:

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


Prove the following identities:

`(1 + (secA - tanA)^2)/(cosecA(secA - tanA)) = 2tanA`


Prove that:

(sin A + cos A) (sec A + cosec A) = 2 + sec A cosec A


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


Eliminate θ, if
x = 3 cosec θ + 4 cot θ
y = 4 cosec θ – 3 cot θ


If \[\sin \theta = \frac{4}{5}\] what is the value of cotθ + cosecθ? 


If \[\sin \theta = \frac{1}{3}\] then find the value of 9tan2 θ + 9. 


If 5x = sec θ and \[\frac{5}{x} = \tan \theta\]find the value of \[5\left( x^2 - \frac{1}{x^2} \right)\] 


Prove the following identity :

secA(1 + sinA)(secA - tanA) = 1


Prove the following identity :

`(1 + sinA)/(1 - sinA) = (cosecA + 1)/(cosecA - 1)`


Prove the following identity : 

`sin^2Acos^2B - cos^2Asin^2B = sin^2A - sin^2B`


Prove the following identity : 

`(cos^3A + sin^3A)/(cosA + sinA) + (cos^3A - sin^3A)/(cosA - sinA) = 2`


Prove the following identity : 

`sin^8θ - cos^8θ = (sin^2θ - cos^2θ)(1 - 2sin^2θcos^2θ)`


If x = asecθ + btanθ and y = atanθ + bsecθ , prove that `x^2 - y^2 = a^2 - b^2`


Prove that sin2 θ + cos4 θ = cos2 θ + sin4 θ.


If tan α = n tan β, sin α = m sin β, prove that cos2 α  = `(m^2 - 1)/(n^2 - 1)`.


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


Prove that identity:
`(sec A - 1)/(sec A + 1) = (1 - cos A)/(1 + cos A)`


Prove the following identities.

`(1 - tan^2theta)/(cot^2 theta - 1)` = tan2 θ


sin2θ + sin2(90 – θ) = ?


If 3 sin θ = 4 cos θ, then sec θ = ?


Prove that sin4A – cos4A = 1 – 2 cos2A.


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


If sin A = `1/2`, then the value of sec A is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×