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Take a Test wil McDowell Google Chrome o Secure https//www.mathpolcom/Student/Player Test aspx?testld-155284514&centerwin; yes Math 123 Spring 2017 TTh Section 3 Quiz: Practice Test 2 This Question: 1 pt 13 of 21 (10 complete) v Find the exact value of the following expression. Do not use a calculator to enter a decimal approximation sin 2x sin 2x (Type an integer or a fraction. Type an exact answer using radicals as needed Rationalize all denominators Enter your answer in the answer box.

Solution

sin (a+b) =sina*cosb+cosa*sinb

let a=b=pi

that implies sin (pi+pi) =sinpi*cospi+sinpi*cospi

= 2 sinpi*cospi

WKT sinpi=0 and cospi =-1

therefore sin2pi=0