Cannotfind7

Ok so to start out, I was given a puzzle to solve under the conditions that i could not solve it by using a scientific calculator. So hitting Sin(x) is not an option.

I was started out with a circle as a base. The circle has a Diameter of 6.5 meters and an idea of putting 80 points along the edge of the circle with the same distance between each of them. I need to find the distance that is between these points, Not the arch curve but the straight line between them.

best way i thought of how to do that was to make a triangle, using the radius for 2 of the sides and finding the link the third and final side through law of sines and law of cosines.

Side a=3.25

Side b=3.25

Side c= X

Angle A= 87.75

Angle B= 87.75

Angle C= 4.5

Sin(a)/A = Sin©/C

Sin©= (C * Sin(a))/A

Sin(x)= (4.5 * Sin(3.25)) /87.75

Now that i have so far, I could solve it if I knew how to solve " Sin(3.25) " by hand I would be set. But I was only taught on how to plug it in to the calculator.

How do you guys solve For Sin(3.25) by hand. Diagrams or links would be helpful so I can better understand how to solve for sin by hand.