SOLUTION: How do i derive the formulas for sin(theta over 2) , Cos(Theta over 2) and Tan(Theta over 2) from a figure

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Question 444866: How do i derive the formulas for sin(theta over 2) , Cos(Theta over 2) and Tan(Theta over 2) from a figure
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!


If , you know that





Also, you know that AD is an angle bisector, so the following ratio holds:


Try combining these to derive the half-angle formulas.