If cos A-1=0, where 0<or= A< 2pi, then A=? The answer I got was pi/3,5pi/3. I don't know where I went wrong can you please help. thanks

Answer 1

cos(A) -1 = 0
or
cos(A) = 1
arccos(1) = A = 0

Answer 2

cot 17= 3.2709 what does tan of 73 equal