(a) Define the term “principal value” of an inverse trigonometric function.
(b) State the principal value ranges of arcsinx, arccosx and arctanx.
(c) For each of the following expressions, decide whether the angle shown is the principal value of the inverse trigonometric expression indicated. Give a brief reason for every answer.
(i) arcsin(21)=65π
(ii) arccos(−43)=32π
(iii) arctan(2)=65π
(d) Rewrite every incorrect equality in part (c) with the correct principal value.