00:01
So we need to find all degree solutions and all solutions between 0 and 360 degrees.
00:07
We cannot use a calculator.
00:09
We're given the equation 2 sine of theta minus root 3 times 2 sine of theta minus 1, and this equals 0.
00:21
So remember we factor equations with trigonometric functions the same way we factor and solve equations with variables.
00:27
So this is saying 2 sine of theta minus root 3 is equal to 0 or 2 sine of theta minus 1 is equal to 0.
00:42
So this gives us that sine of theta is equal to root 3 over 2 and sine of theta or sine of theta is equal to 1 1 half.
00:55
So let's look at root 3 over 2 first.
00:59
Sign is positive in quadrant 1 and quadrant 2.
01:04
And we know that sine of theta is equal to root 3 over 2 when theta is equal to 60 degrees.
01:21
We also know, so that is in quadrant 1, so in quadrant 2 the angle would be 120 degrees...