In the rectangular coordinate plane, the angle between the line between the point P (4.1) and the origin O and the positive half axis of the x-axis is α

In the rectangular coordinate plane, the angle between the line between the point P (4.1) and the origin O and the positive half axis of the x-axis is α

Make PE ⊥ X axis intersect X axis at point E
Then PE = 1, OE = 4, Po = √ 17
So tan α = PE / OE = 1 / 4
cotα=1/tanα=4
sinα=PE/PO=√17/17
cosα=OE/PO=4√17/17