English

Find the General Solution of the Following Equation: Sin 9 X = Sin X - Mathematics

Advertisements
Advertisements

Question

Find the general solution of the following equation:

\[\sin 9x = \sin x\]
Sum
Advertisements

Solution

We have:

\[\sin9x = \sin x\]

⇒ \[\sin9x - \sin x = 0\]

⇒ \[2 \sin \left( \frac{9x - x}{2} \right) \cos \left( \frac{9x + x}{2} \right) = 0\]

⇒ \[\sin \frac{8x}{2} = 0\] or \[\cos \frac{10x}{2} = 0\]

⇒ \[\sin 4x = 0\] or \[\cos 5x = 0\]

⇒ \[4x = n\pi\]

\[n \in Z\] or \[5x = (2n + 1)\frac{\pi}{2}\],

\[n \in Z\]

⇒ \[x = \frac{n\pi}{4}\],

\[n \in Z\] or \[x = (2n + 1)\frac{\pi}{10}\],

\[n \in Z\]
shaalaa.com
  Is there an error in this question or solution?
Chapter 11: Trigonometric equations - Exercise 11.1 [Page 21]

APPEARS IN

RD Sharma Mathematics [English] Class 11
Chapter 11 Trigonometric equations
Exercise 11.1 | Q 2.03 | Page 21

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

Prove that: tan (−225°) cot (−405°) −tan (−765°) cot (675°) = 0


Find x from the following equations:
\[cosec\left( \frac{\pi}{2} + \theta \right) + x \cos \theta \cot\left( \frac{\pi}{2} + \theta \right) = \sin\left( \frac{\pi}{2} + \theta \right)\]


Find x from the following equations:
\[x \cot\left( \frac{\pi}{2} + \theta \right) + \tan\left( \frac{\pi}{2} + \theta \right)\sin \theta + cosec\left( \frac{\pi}{2} + \theta \right) = 0\]


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:

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

If x = r sin θ cos ϕ, y = r sin θ sin ϕ and r cos θ, then x2 + y2 + z2 is independent of


If tan \[x = - \frac{1}{\sqrt{5}}\] and θ lies in the IV quadrant, then the value of cos x is

 

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

 

If A lies in second quadrant 3tan A + 4 = 0, then the value of 2cot A − 5cosA + sin A is equal to


If \[cosec x + \cot x = \frac{11}{2}\], then tan x =

 


Which of the following is correct?


Find the general solution of the following equation:

\[\tan 3x = \cot x\]

Solve the following equation:

\[2 \cos^2 x - 5 \cos x + 2 = 0\]

Solve the following equation:

\[\cos x + \cos 3x - \cos 2x = 0\]

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


If secx cos5x + 1 = 0, where \[0 < x \leq \frac{\pi}{2}\], find the value of x.


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
\[4 \sin x - 3 \cos x = 7\]


Write the number of points of intersection of the curves

\[2y = - 1 \text{ and }y = cosec x\]

Write the number of values of x in [0, 2π] that satisfy the equation \[\sin x - \cos x = \frac{1}{4}\].


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

 


If \[\tan px - \tan qx = 0\], then the values of θ form a series in

 


A value of x satisfying \[\cos x + \sqrt{3} \sin x = 2\] is

 

If \[\cos x = - \frac{1}{2}\] and 0 < x < 2\pi, then the solutions are


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:
tan θ = `- 1/sqrt(3)`


Solve the following equations for which solution lies in the interval 0° ≤ θ < 360°

cos 2x = 1 − 3 sin x


Solve the following equations:
cos θ + cos 3θ = 2 cos 2θ


Solve the following equations:
cot θ + cosec θ = `sqrt(3)`


Solve the following equations:
cos 2θ = `(sqrt(5) + 1)/4`


Choose the correct alternative:
If tan α and tan β are the roots of x2 + ax + b = 0 then `(sin(alpha + beta))/(sin alpha sin beta)` 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 ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×