Useful trig double angle formulas to save you time when integrating.
1 =
sin²(x) + cos²(x)
csc²(x) =
1 + cot²(x)
sec²(x) =
tan²(x) + 1
2sin(x)cos(x) =
sin(2x)
cos²(x) - sin²(x) =
cos(2x)
1 - 2sin²(x) =
cos(2x)
2cos²(x) - 1 =
cos(2x)
2tan(x) / (1 - tan²(x)) =
tan(2x)
(1 - cos(2x)) / 2 =
sin²(x)
(1 + cos(2x)) / 2 =
cos²(x)