How do I simplify 2sin(100pi/9)*cos(100pi/9)?

1 Answer
Aug 6, 2018

color(indigo)(=>sin ((200pi)/9) = sin ((2pi)/9)

Explanation:

https://artofproblemsolving.com/wiki/index.php?title=Trigonometric_identitieshttps://artofproblemsolving.com/wiki/index.php?title=Trigonometric_identities

sin 2alpha = 2 sin alpha cos alpha

:. 2 * sin ((100pi)/9) * cos ((100pi)/9) = sin (2* ((100pi)/9))

color(indigo)(=>sin ((200pi))/9 = sin ((2pi)/9)