.Hi

I have a few questions in can't get the right answers:

1)Simply the expression Note that this is the difference of squares.

2)Simply the expression Factor out a tanx, then note that (tan^2x+1)=sec^2x. What you have done is unneccesary.

This is what i have done:

=

=

what should i do next?

3)if tanx=-4,x [ ] find: sec(x)

P.S