हिंदी

If T N = Sin N X + Cos N X , Prove that T 3 − T 5 T 1 = T 5 − T 7 T 3 - Mathematics

Advertisements
Advertisements

प्रश्न

If \[T_n = \sin^n x + \cos^n x\], prove that \[\frac{T_3 - T_5}{T_1} = \frac{T_5 - T_7}{T_3}\]

 

Advertisements

उत्तर

LHS:\[\frac{T_3 - T_5}{T_1} = \frac{\left( \sin^3 x + \cos^3 x \right) - \left( \sin^5 x + \cos^5 x \right)}{\sin x + \cos x}\]
\[ = \frac{\sin^3 x - \sin^5 x + \cos^3 x - \cos^5 x}{\sin x + \cos x}\]
\[ = \frac{\sin^3 x\left( 1 - \sin^2 x \right) + \cos^3 x\left( 1 - \cos^2 x \right)}{\sin x + \cos x}\]
\[ = \frac{\sin^3 x . \cos^2 x + c {os}^3 x . \sin^2 x}{\sin x + \cos x}\]
\[ = \frac{\sin^2 x . \cos^2 x\left( \sin x + cos x \right)}{\sin x + \cos x}\]
\[ = \sin^2 x . \cos^2 x\]
RHS:  \[\frac{T_5 - T_7}{T_3}\]
\[ = \frac{\left( \sin^5 x + \cos^5 x \right) - \left( \sin^7 x + \cos^7 x \right)}{\sin^3 x + \cos^3 x}\]
\[ = \frac{\sin^5 x - si n^7 x + \cos^5 x - \cos^7 x}{\sin^3 x + \cos^3 x}\]
\[ = \frac{\sin^5 x\left( 1 - \sin^2 x \right) + \cos^5 x\left( 1 - \cos^2 x \right)}{\sin^3 x + \cos^3 x}\]
\[ = \frac{\sin^5 x \cos^2 x + \cos^5 x \sin^2 x}{\sin^3 x + \cos^3 x}\]
\[ = \sin^2 x . \cos^2 x\]
LHS = RHS
Hence proved.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 5: Trigonometric Functions - Exercise 5.1 [पृष्ठ १९]

APPEARS IN

आरडी शर्मा Mathematics [English] Class 11
अध्याय 5 Trigonometric Functions
Exercise 5.1 | Q 26.1 | पृष्ठ १९

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

Find the general solution of the equation sin 2x + cos x = 0


If \[x = \frac{2 \sin x}{1 + \cos x + \sin x}\], then prove that

\[\frac{1 - \cos x + \sin x}{1 + \sin x}\] is also equal to a.

If \[\tan x = \frac{a}{b},\] show that

\[\frac{a \sin x - b \cos x}{a \sin x + b \cos x} = \frac{a^2 - b^2}{a^2 + b^2}\]

If \[cosec x - \sin x = a^3 , \sec x - \cos x = b^3\], then prove that \[a^2 b^2 \left( a^2 + b^2 \right) = 1\]


Prove that:
\[\frac{\cos (2\pi + x) cosec (2\pi + x) \tan (\pi/2 + x)}{\sec(\pi/2 + x)\cos x \cot(\pi + x)} = 1\]

 


Prove that

\[\frac{\tan (90^\circ - x) \sec(180^\circ - x) \sin( - x)}{\sin(180^\circ + x) \cot(360^\circ - x) cosec(90^\circ - x)} = 1\]

 


Prove that:
\[\sec\left( \frac{3\pi}{2} - x \right)\sec\left( x - \frac{5\pi}{2} \right) + \tan\left( \frac{5\pi}{2} + x \right)\tan\left( x - \frac{3\pi}{2} \right) = - 1 .\]


Prove that:
\[\tan 4\pi - \cos\frac{3\pi}{2} - \sin\frac{5\pi}{6}\cos\frac{2\pi}{3} = \frac{1}{4}\]


Prove that:

\[\sin\frac{10\pi}{3}\cos\frac{13\pi}{6} + \cos\frac{8\pi}{3}\sin\frac{5\pi}{6} = - 1\]

\[\sec^2 x = \frac{4xy}{(x + y )^2}\] is true if and only if

 


sin2 π/18 + sin2 π/9 + sin2 7π/18 + sin2 4π/9 =


If x sin 45° cos2 60° = \[\frac{\tan^2 60^\circ cosec30^\circ}{\sec45^\circ \cot^{2^\circ} 30^\circ}\], then x =

 

If \[f\left( x \right) = \cos^2 x + \sec^2 x\], then


The value of \[\cos1^\circ \cos2^\circ \cos3^\circ . . . \cos179^\circ\] is

 

Which of the following is correct?


Find the general solution of the following equation:

\[\cos x = - \frac{\sqrt{3}}{2}\]

Find the general solution of the following equation:

\[\cos 3x = \frac{1}{2}\]

Solve the following equation:

\[\cos x + \sin x = \cos 2x + \sin 2x\]

Solve the following equation:

\[\tan x + \tan 2x + \tan 3x = 0\]

Solve the following equation:
\[\sin x - 3\sin2x + \sin3x = \cos x - 3\cos2x + \cos3x\]


Solve the following equation:
 cosx + sin x = cos 2x + sin 2x

 


Write the number of solutions of the equation tan x + sec x = 2 cos x in the interval [0, 2π].


Write the number of solutions of the equation
\[4 \sin x - 3 \cos x = 7\]


If \[3\tan\left( x - 15^\circ \right) = \tan\left( x + 15^\circ \right)\] \[0 < x < 90^\circ\], find θ.


If \[2 \sin^2 x = 3\cos x\]. where \[0 \leq x \leq 2\pi\], then find the value of x.


The smallest value of x satisfying the equation

\[\sqrt{3} \left( \cot x + \tan x \right) = 4\] is 

If \[\cos x + \sqrt{3} \sin x = 2,\text{ then }x =\]

 


The general value of x satisfying the equation
\[\sqrt{3} \sin x + \cos x = \sqrt{3}\]


If \[4 \sin^2 x = 1\], then the values of x are

 


If \[\cot x - \tan x = \sec x\], then, x is equal to

 


In (0, π), the number of solutions of the equation ​ \[\tan x + \tan 2x + \tan 3x = \tan x \tan 2x \tan 3x\] is 


The equation \[3 \cos x + 4 \sin x = 6\] has .... solution.


The number of values of x in the interval [0, 5 π] satisfying the equation \[3 \sin^2 x - 7 \sin x + 2 = 0\] is


Find the principal solution and general solution of the following:
sin θ = `-1/sqrt(2)`


Choose the correct alternative:
If sin α + cos α = b, then sin 2α is equal to


Solve 2 tan2x + sec2x = 2 for 0 ≤ x ≤ 2π.


If sin θ and cos θ are the roots of the equation ax2 – bx + c = 0, then a, b and c satisfy the relation ______.


Find the general solution of the equation 5cos2θ + 7sin2θ – 6 = 0


The minimum value of 3cosx + 4sinx + 8 is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×