Let's verify the identity

What happens when we multiply the right hand side by

** A. ** ** B. ** ** C. ** ** D. ** ** E. ** None of the above

How can we use double angle formulas to simplify the right hand side?

** A. ** ** B. ** ** C. ** ** D. ** ** E. ** None of the above

How can we finish the proof?

** A. ** The previous equation is true after multiplying both sides by tangent.** B. ** The previous equation is equivalent to the Pythagorean Theorem.** C. ** The previous equation is true by the definition of sine and cosine.** D. ** The previous equation is true by the definition of the double angle formulas.** E. ** The previous equation is true by the definition of tangent.** F. ** None of the above