1) What is the value of arccos x as x approaches 1 from the left?
2) What is the value of arcsin x as x approaches -1 from the right?
3) What is the value of arctan x as x approaches negative infinity?
Being familiar with the basic sine, cosine and tangent curves
we should see that:
1) 0
2) -90° or -π/2
3) -90° or -π/2