SOLUTION: tan 490 degrees as a function of an angle less than 45 degrees is: Answers: a) tangent 40 degrees b) - tangent 40 degrees c) cot 40 degrees d) - cot 40 degrees

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Question 824301: tan 490 degrees as a function of an angle less than 45 degrees is:
Answers:
a) tangent 40 degrees
b) - tangent 40 degrees
c) cot 40 degrees
d) - cot 40 degrees
Answer by fcabanski(1391) About Me  (Show Source):
You can put this solution on YOUR website!
490 - 360 = 130. 130 is 50 degrees from 180 (180-130=50). Thus the reference angle is 50 degrees in the second quadrant. So tan is negative.


But the question asks for an angle less than 45. Use the cofunction identity tan(90-x) = cot(x). 50 = 90-40. Remember, it has to be negative, because it's in the second quadrant.


tan(490) = - tan(90-40) = -cot(40)