SOLUTION: Arctan(1) + Arcsin(0) + Arccos{{{(sqrt(3)/2)}}}

Arctan(1) + Arcsin(0) + Arccos

Arctan(1) = ? asks tan(?) = 1 ---> answer: 45° or  radians

Arcsin(0) = ? asks sin(?) = 0 ---> answer: 0°  or 0 radians

Arccos = ? asks cos(?) =  ---> answer: 30° or  radians

So, if your answer is to be in degrees:

Arctan(1) + Arcsin(0) + Arccos = 45° + 0° + 30° = 75°    

Or if your answer is to be in radians:

Arctan(1) + Arcsin(0) + Arccos =  +  +  =  +  =  +  = 

Edwin