Will mark the ! lots of now find the following ( give the exact value where appropriate) a) cos (arctan (1))= and the angle is in quadrant 111 b) sin (arccos (1/2)= if the angle is in quadrant iv

cos (arctan (1))=

arctan (1) = 45   take it to the third quadrant = add 180  = 225

cos (225) = -1 / sqrt(2)

            never leave a sqrt in the denominator

     = -1 /sqrt(2) * sqrt(2)/sqrt(2)

   = -sqrt(2)/2

sin (arccos (1/2)

arccos (1/2) = 60    take it to the 4th quadrant   -60 degrees

sin (-60)

- sin 60

- sqrt(3)/2

something over 10 so ? /10

step-by-step explanation:

actually what is a question i don't understand