What is the exact value of cot(5pi/6)?

3 answers

If you draw the angle, then draw a line down to the x axis, you will find that your reference angle is pi/6.

tan(pi/6) should be a memory value; cot is its reciprocal. Remember that your angle is in Quadrant II.
I'm sorry, I'm still confused :s
I cannot post images here - you'll have to draw it yourself.

1. Draw the units circle, then draw the angle 5pi/6.

2. draw a line from that angle to the x axis

3. The angle of the resulting triangle is your reference angle.

Can you get that far?