The question I don't get is:
"For which of the trigonometric points defined in the previous question is it impossible to calculate:
a) the tangent?
b) the cosecant?
c) the secant?
d) the cotangent?"
the previous question was:
"Without using a calculator, give the coordinats of the trigonometric point corresponding to a central angle that measures"
Any help would be GREATLY appreciated!