Those are too many questions because each answer is very long.
I will do b for you and that should help you to figure out how to do the others.
b) 1 - cos(2x)
----------------- = tan(x)
sin(2x)
1 - [cos^2 (x) - sin^2 (x) ]
---------------------------------- = tan(x)
2 cos(x)(sin(x)
1 - cos^2(x) + sin^2(x)
----------------------------- = tan(x)
2cos(x)sin(x)
[1 - cos^2(x) ] + sin^2(x)
-------------------------------- = tan(x)
2cos(x)sin(x)
sin^2(x) + sin^2 (x)
-------------------------- = tan(x)
2cos(x)(sin(x)
2 sin^2 (x)
--------------------- = tan(x)
2 cos(x)sin(x)
sin(x)
----------- = tan(x)
cos(x)
tan(x) = tan(x)