WBJEE · Maths · Trigonometric Equations
If \(\sin 6 \theta+\sin 4 \theta+\sin 2 \theta=0\) then the general value of \(\theta\) is
- A \(\frac{\mathrm{n} \pi}{4}, \mathrm{n} \pi \pm \frac{\pi}{3}\)
- B \(\frac{\mathrm{n} \pi}{4}, \mathrm{n} \pi \pm \frac{\pi}{6}\)
- C \(\frac{\mathrm{n} \pi}{4}, 2 \mathrm{n} \pi \pm \frac{\pi}{3}\)
- D \(\frac{\mathrm{n} \pi}{4}, 2 \mathrm{n} \pi \pm \frac{\pi}{6}\)
Answer & Solution
Correct Answer
(A) \(\frac{\mathrm{n} \pi}{4}, \mathrm{n} \pi \pm \frac{\pi}{3}\)
Step-by-step Solution
Detailed explanation
Hints : \(2 \sin 4 \theta \cos 2 \theta+\sin 4 \theta=0\) \(\sin 4 \theta=0\) \(2 \cos 2 \theta=-1\) \(4 \theta=n \pi\) \(\cos 2 \theta=-\frac{1}{2}=\cos \frac{2 \pi}{3}\) \(\theta=\frac{n \pi}{4}\)…
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