How do you solve $sin3x=1/2$ ?

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Answer 1 · 2015-06-09T07:17:31

From angle table

You know that

$sin(30^@)=1/2$

In your equation, you have

$sin(3x)=1/2$

Since both equations are equal to the same value, you can write

$sin(3x) =sin(30^@)$

This implies that

$3x=30^@ => x = 30^@/3 = 10^@$

Answer 2 · 2015-06-09T18:07:47

$10^@, 50^@$

$sin 3x = 1/2$
Trig table of special arcs gives
$3x = 30^@$
$x = 10^@$

The trig unit circle gives another arc x that has the same sin value:
$3x = (180 - 30) = 150^@$
$x = 50^@$
Answers for (0, 360):
$10^@, 50^@$

How do you solve sin3x=1/2sin3x=1/2?