Answer: A and B
pi/3 and 2pi/3
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Work Shown:
2*sin(x) - sqrt(3) = 0
2sin(x) = sqrt(3)
sin(x) = sqrt(3)/2
Using the unit circle, we see that sin(theta) is equal to sqrt(3)/2 when theta is theta = pi/3 in quadrant I, and when theta = 2pi/3 in quadrant II.
So sin(pi/3) = sqrt(3)/2 and sin(2pi/3) = sqrt(3)/2
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You can check these answers by replacing x with the value in question and seeing if you get zero. Make sure your calculator is in radian mode
Plug in x = pi/3
2*sin(x) - sqrt(3) = 0
2*sin(pi/3) - sqrt(3) = 0
0 = 0 .................... this is a true equation, x = pi/3 is confirmed as a solution
Plug in x = 2pi/3
2*sin(x) - sqrt(3) = 0
2*sin(2pi/3) - sqrt(3) = 0
0 = 0 .................... true equation, x = 2pi/3 is confirmed as a solution
Plug in x = 4pi/3
2*sin(x) - sqrt(3) = 0
2*sin(4pi/3) - sqrt(3) = 0
-3.4641016 = 0 ............ false equation, x = 4pi/3 is a nonsolution
Plug in x = 5pi/3
2*sin(x) - sqrt(3) = 0
2*sin(5pi/3) - sqrt(3) = 0
-3.4641016 = 0 ............ false equation, x = 5pi/3 is a nonsolution