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They want you calculate sin(480°) + tan(390°).
The angle 480° is more than 1 full rotation, which, as you should know, is 360°.
So, the angle of 480° is equivalent to 480° - 360° = 120°, and sin(480°) = sin(120°).
What is sin(120°), knows every student: it is .
The angle 390° is also more than 1 full rotation and is equivalent to 390° - 360° = 30°.
Therefore, tan(390°) = tan(30°). What is tan(30°), knows any student: it is .
Therefore, the ANSWER to the problem's question is
sin(480°) + tan(390°) = + .
You may transform this expression further, if you want or if you need.
Solved, answered, explained and completed.
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