trig question

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1

<p>not really SAT related, but can someone help me understand this:</p>

<p>arctan(-sqrt(3))</p>

<p>can the angle be both 120 degrees and -60 degrees?</p>

2

<p>yes, because tan is negative in the second and fourth quadrants. instead of writing -60 degrees, 300 degrees is a better way of putting it.</p>

3

<p>No, the answer is -60, because arctan has a restricted domain between -90 and 90. If the question was tanx=-sqrt3, then it is 120 and -60.</p>

4

<p>

This ^</p>

<p>The reason the domain is restricted is that otherwise the arctan wouldn’t be a function. All the inverse trig functions are restricted in some way.</p>