हिंदी

If cos^−1(xa)+cos^−1(yb)=α , prove that x2/a2−2 xy/ab cosα+y^2/b^2=sin^2 α - Mathematics

Advertisements
Advertisements

प्रश्न

If `cos^-1( x/a) +cos^-1 (y/b)=alpha` , prove that `x^2/a^2-2(xy)/(ab) cos alpha +y^2/b^2=sin^2alpha`

Advertisements

उत्तर

`cos^-1( x/a) +cos^-1 (y/b)=alpha` 

`cos^-1(x/a) =alpha-cos^-1 (y/b)`

`=>cos {cos^-1 (x/a)}=cos{alpha-cos^-1 (y/b)}`

`=>x/a=cos alpha cos{cos^-1 (y/b)}+sinalpha sin{cos^-1(y/b)}`

`=>x/a=y/b cos alpha+sin alpha sqrt(1-(y/b)^2)`

`=>x/a - y/b cos alpha =sin alpha sqrt(1-(y/b)^2)`

Squaring both sides, we get

`(x/a - y/b cos alpha)^2={sin alpha sqrt(1-(y/b)^2)}^2`

`(x/a)^2+(y/b)^2cos^2 alpha- (2xy)/(ab) cos alpha=sin^2 alpha- sin^2 alpha(y/b)^2`

`(x/a)^2+(y/b)^2cos^2 alpha+sin^2 alpha(y/b)^2-(2xy)/(ab) cos alpha=sin^2 alpha`

`(x/a)^2+(y/b)^2(cos^2 alpha+sin^2 alpha)-(2xy)/(ab) cos alpha=sin^2 alpha`

`=>(x/a)^2-(2xy)/(ab) cos alpha+(y/b)^2=sin^2 alpha`

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
2015-2016 (March) All India Set 2 C

वीडियो ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्न

If (tan1x)2 + (cot−1x)2 = 5π2/8, then find x.


Evaluate the following:

`cos^-1{cos  ((4pi)/3)}`


Evaluate the following:

`cos^-1(cos3)`


Evaluate the following:

`cos^-1(cos12)`


Evaluate the following:

`tan^-1(tan  (9pi)/4)`


Evaluate the following:

`sec^-1{sec  (-(7pi)/3)}`


Write the following in the simplest form:

`tan^-1(x/(a+sqrt(a^2-x^2))),-a<x<a`


Evaluate the following:

`cosec(cos^-1  3/5)`


Prove the following result

`tan(cos^-1  4/5+tan^-1  2/3)=17/6`


Prove the following result-

`tan^-1  63/16 = sin^-1  5/13 + cos^-1  3/5`


Evaluate:

`sec{cot^-1(-5/12)}`


Evaluate:

`cosec{cot^-1(-12/5)}`


Evaluate: `sin{cos^-1(-3/5)+cot^-1(-5/12)}`


`sin(sin^-1  1/5+cos^-1x)=1`


Solve the following equation for x:

`tan^-1  x/2+tan^-1  x/3=pi/4, 0<x<sqrt6`


Evaluate: `cos(sin^-1  3/5+sin^-1  5/13)`


Evaluate the following:

`sin(2tan^-1  2/3)+cos(tan^-1sqrt3)`


Prove that:

`2sin^-1  3/5=tan^-1  24/7`


Solve the following equation for x:

`cos^-1((x^2-1)/(x^2+1))+1/2tan^-1((2x)/(1-x^2))=(2x)/3`


For any a, b, x, y > 0, prove that:

`2/3tan^-1((3ab^2-a^3)/(b^3-3a^2b))+2/3tan^-1((3xy^2-x^3)/(y^3-3x^2y))=tan^-1  (2alphabeta)/(alpha^2-beta^2)`

`where  alpha =-ax+by, beta=bx+ay`


Write the value of cos−1 \[\left( \cos\frac{5\pi}{4} \right)\]


Evaluate: \[\sin^{- 1} \left( \sin\frac{3\pi}{5} \right)\]


If \[\tan^{- 1} (\sqrt{3}) + \cot^{- 1} x = \frac{\pi}{2},\] find x.


If 4 sin−1 x + cos−1 x = π, then what is the value of x?


What is the principal value of `sin^-1(-sqrt3/2)?`


2 tan−1 {cosec (tan−1 x) − tan (cot1 x)} is equal to


\[\tan^{- 1} \frac{1}{11} + \tan^{- 1} \frac{2}{11}\]  is equal to

 

 


The value of \[\sin^{- 1} \left( \cos\frac{33\pi}{5} \right)\] is 

 


The value of  \[\sin\left( 2\left( \tan^{- 1} 0 . 75 \right) \right)\] is equal to

 


tanx is periodic with period ____________.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×