हिंदी

Solve the Following Equation: Sin X + Sin 2 X + Sin 3 = 0 - Mathematics

Advertisements
Advertisements

प्रश्न

Solve the following equation:

\[\sin x + \sin 2x + \sin 3 = 0\]
योग
Advertisements

उत्तर

\[\sin x + \sin 2x + \sin 3 = 0\]
\[\Rightarrow \sin x + \sin3x + \sin2x = 0\]
\[ \Rightarrow 2 \sin \left( \frac{4x}{2} \right) \cos \left( \frac{2x}{2} \right) + \sin2x = 0\]
\[ \Rightarrow 2 \sin2x\cos x + \sin2x = 0\]
\[ \Rightarrow \sin2x (2 \cos x + 1) = 0\]

\[\Rightarrow \sin2x = 0\] or
\[2 \cos x + 1 = 0\]
\[\Rightarrow \sin2x = \sin 0\] or
\[\cos x = - \frac{1}{2} \Rightarrow \cos x = \cos \frac{2\pi}{3}\]
⇒ \[x = \frac{n\pi}{2}, n \in Z\] or
\[x = 2m\pi \pm \frac{2\pi}{3}\],
\[m \in Z\]
shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 11: Trigonometric equations - Exercise 11.1 [पृष्ठ २२]

APPEARS IN

आरडी शर्मा Mathematics [English] Class 11
अध्याय 11 Trigonometric equations
Exercise 11.1 | Q 4.6 | पृष्ठ २२

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

Find the general solution of the equation  sin x + sin 3x + sin 5x = 0


If \[\sin x + \cos x = m\], then prove that \[\sin^6 x + \cos^6 x = \frac{4 - 3 \left( m^2 - 1 \right)^2}{4}\], where \[m^2 \leq 2\]


Prove that:

\[\sin\frac{8\pi}{3}\cos\frac{23\pi}{6} + \cos\frac{13\pi}{3}\sin\frac{35\pi}{6} = \frac{1}{2}\]

 


Prove that: \[\tan\frac{11\pi}{3} - 2\sin\frac{4\pi}{6} - \frac{3}{4} {cosec}^2 \frac{\pi}{4} + 4 \cos^2 \frac{17\pi}{6} = \frac{3 - 4\sqrt{3}}{2}\]

 


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


In a ∆ABC, prove that:

\[\tan\frac{A + B}{2} = \cot\frac{C}{2}\]

In a ∆A, B, C, D be the angles of a cyclic quadrilateral, taken in order, prove that cos(180° − A) + cos (180° + B) + cos (180° + C) − sin (90° + D) = 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:

\[\tan\frac{5\pi}{4}\cot\frac{9\pi}{4} + \tan\frac{17\pi}{4}\cot\frac{15\pi}{4} = 0\]

 


\[\sqrt{\frac{1 + \cos x}{1 - \cos x}}\] is equal to

 


sin6 A + cos6 A + 3 sin2 A cos2 A =


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

 


Which of the following is incorrect?


Find the general solution of the following equation:

\[\sin 2x = \frac{\sqrt{3}}{2}\]

Find the general solution of the following equation:

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

Solve the following equation:

\[\sin x + \sin 5x = \sin 3x\]

Solve the following equation:
4sinx cosx + 2 sin x + 2 cosx + 1 = 0 


Solve the following equation:
3sin2x – 5 sin x cos x + 8 cos2 x = 2


Solve the following equation:
\[2^{\sin^2 x} + 2^{\cos^2 x} = 2\sqrt{2}\]


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 set of values of a for which the equation

\[\sqrt{3} \sin x - \cos x = a\] has no solution.

Write the values of x in [0, π] for which \[\sin 2x, \frac{1}{2}\]

 and cos 2x are in A.P.


The general solution of the equation \[7 \cos^2 x + 3 \sin^2 x = 4\] is


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


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


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


Solve the following equations:
`tan theta + tan (theta + pi/3) + tan (theta + (2pi)/3) = sqrt(3)`


Choose the correct alternative:
If tan 40° = λ, then `(tan 140^circ - tan 130^circ)/(1 + tan 140^circ *  tan 130^circ)` =


Choose the correct alternative:
If cos pθ + cos qθ = 0 and if p ≠ q, then θ is equal to (n is any integer)


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


Choose the correct alternative:
If f(θ) = |sin θ| + |cos θ| , θ ∈ R, then f(θ) is in the interval


Choose the correct alternative:
`(cos 6x + 6 cos 4x + 15cos x + 10)/(cos 5x + 5cs 3x + 10 cos x)` is equal to


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


In a triangle ABC with ∠C = 90° the equation whose roots are tan A and tan B is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×