The general solution of sin , x + sin ,5x = sin , 2x + sin ,4x is… - Vidyadip

MCQ

The general solution of $sin\, x + sin \,5x = sin\, 2x + sin \,4x$ is :

A
$2n\pi$
B
$n\pi$
✓
$n\pi /3$
D
$2 n\pi /3$ where $n \in I$

✓

Answer

Correct option: C.

$n\pi /3$

c
$sinx + sin5x = sin2x + sin4x$

$2 \,sin3x \, cos2x = 2\, sin3x \,cosx$

$2sin3x [ cos2x - cosx] = 0$

On solving we get $x = n\pi /3$

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