we inow the values e sn and conwecan find the vah orm2r by u

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Solution

1. sin (2x) = 2 sin(x) cos(x)

2. sin(x/2) = +_ sqrt( ( 1-cos(x)) /2 )

3. sin x = 5/13 ; opp side = 5 ; hypotenuse = 13 ; adjacent side = 12

sin(2x) = 2. 5/13 . 12/13 = 120 / 169

cos(2x) = cos ^2 x - sin^2 x = 144 /169 - 25 / 169 = 119 /169

tan(2x) = sin(2x) / cos(2x) = 120 / 119

4. tan (x ) = -12/5 in quadrant 2

sin (x) = 12/13 ; cos(x) = -5/13

sin(2x) = -120/169 ; cos(2x) = -119/169 ; tan(2x) = 120 / 119

8. sin (x) = 1/2 ; x = pie/6 radians

9.sin(x) = -1/sqrt(2) ; x = 5 pie/4 radians

10.cos(x) = -1 ; x = pie radians

14. theta = pie , pie/3