How do you evaluate $sin(arctan(2))$ ?

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Answer 1 · 2015-05-21T12:48:07

Call x the $(arc(tan 2))$ . Calculator gives:

tan x = 2 --> $x = 63.43 deg$

The trig unit circle gives another arc x that has the same tan value:

x = 63.43 + 180 = $243.43 deg$

a. $sin x = sin (63,43) = 0.89$

b. $sin x = sin (243.43) = -sin (63.43) = -0.89$

How do you evaluate sin(arctan(2))sin(arctan(2))?