हिंदी

If x = a cos^3θ and y = b sin^3θ, prove that (x/a)^(2/3) + (y/b)^(2/3) = 1.

Advertisements
Advertisements

प्रश्न

If x = a cos3θ and y = b sin3θ, prove that `(x/a)^(2/3) + (y/b)^(2/3) = 1`.

प्रमेय
Advertisements

उत्तर

We have x = a `cos^3 theta `

 = > `x/a = cos^3 theta     ........(i)`

 Again, `y = b  sin^3 theta`

  =  > `y/b = sin^3 theta      .....(ii)`

 Now, LHS = `(x/a)^(2/3) + (y/b)^(2/3)`

 = `( cos^3 theta )^(2/3) + (sin^3 theta )^ (2/3 )`     [ from (i) and (ii)]

 =` cos^2 theta + sin^2 theta `

 =1

𝐻𝑒𝑛𝑐𝑒, 𝐿𝐻𝑆 = 𝑅𝐻𝑆       

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 11: Trigonometric Identities - EXERCISE 11.1 [पृष्ठ ११.३६]

APPEARS IN

आर.डी. शर्मा Mathematics [English] Class 10
अध्याय 11 Trigonometric Identities
EXERCISE 11.1 | Q 45. | पृष्ठ ११.३६
आर.एस. अग्रवाल Mathematics [English] Class 10
अध्याय 13 Trigonometric identities
EXERCISE 13В | Q 4. | पृष्ठ ६२८

संबंधित प्रश्न

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


Prove the following trigonometric identities:

(1 + tan2 θ) (1 − sin θ) (1 + sin θ) = 1


Prove the following trigonometric identities.

sin2 A cos2 B − cos2 A sin2 B = sin2 A − sin2 B


Prove the following identities:

`sqrt((1 - cosA)/(1 + cosA)) = cosec A - cot A`


Prove that:

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


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


From the figure find the value of sinθ.


What is the value of (1 − cos2 θ) cosec2 θ? 


If cosec2 θ (1 + cos θ) (1 − cos θ) = λ, then find the value of λ. 


(cosec θ − sin θ) (sec θ − cos θ) (tan θ + cot θ) is equal to


Prove the following identity : 

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


Prove the following identity :

`(cosA + sinA)^2 + (cosA - sinA)^2 = 2`


Given `cos38^circ sec(90^circ - 2A) = 1` , Find the value of <A


If sin θ = `1/2`, then find the value of θ. 


If A = 30°, verify that `sin 2A = (2 tan A)/(1 + tan^2 A)`.


Prove the following identities:

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


Prove that cos2θ . (1 + tan2θ) = 1. Complete the activity given below.

Activity:

L.H.S. = `square`

= `cos^2θ xx square`   ...`[1 + tan^2θ = square]`

= `(cos θ xx square)^2`

= 12

= 1

= R.H.S.


If `sec θ + tan θ = sqrt(3)`, complete the activity to find the value of sec θ – tan θ.

Activity:

`square = 1 + tan^2θ`   ...[Fundamental trigonometric identity]

`square - tan^2θ = 1`

`(sec θ + tan θ) . (sec θ - tan θ) = square`

`sqrt(3)  . (sec θ - tan θ) = 1`

`(sec θ - tan θ) = square`


Prove that cot2θ – tan2θ = cosec2θ – sec2θ.


Prove the following trigonometry identity:

(sin θ + cos θ)(cosec θ – sec θ) = cosec θ ⋅ sec θ – 2 tan θ


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×