
William W. answered 11/07/23
Experienced Tutor and Retired Engineer
cos-1(√3) or arccos(√3) means, "what angle results in a cosine of √3"? Positive values of cosine are found in Q1 and Q4 but arccos has ranges only in Q1 and Q2 therefore we MUST be in Q1. HOWEVER, √3 is a number approx equal to 1.7 and cosine of any angle only results in numbers between -1 and 1 therefore, there are NO angles that give us values of 1.7 making this impossible.