Trig problems
posted by Sophie .
Part 1)
Evaluate tan 7.5
Part 2)
Evaluate exactly cos ((45pi(4)))

1. I recommend usng a calculator (in radians mode) or search Google with
< tan 7.5 = > in the search window.
2. Remember that you can subtract multiples of 2 pi from the argument of any trig function and get the same answer.
45 pi*4 = 180 pi; the cosine of that is the same as the cosine of zero.
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