1)(1-cos^2x)(csc x) ?

Is this equal to sec x?

2) Expand: log7 3 sqrt x / x^2y

3) Find and simplify: f(g)

F(x) = x^2 + 2x g(x) = 2x

x^2 + 2x(2x) = x^2 + 4x
Is this correct?

see

http://www.jiskha.com/display.cgi?id=1268686417