# Thread: urgent help needed! simplifying expressions...

1. ## urgent help needed! simplifying expressions...

HELP! I'm in Math 12 and have a unit exam soon; the questions on my review all seem to be ones I don't have in my notes and can't understand. A couple I've been struggling with for an hour. Can anyone explain how to do these?

1. sec(-1)-sec(-x)sin*squared*x

So far, I got to:

=sec-1+secxsin*squared*x

=___1____ -1 + __1sin*squared*x__
cosx ************* cosx
=___1___ - __sin*squared*x__
cosx ************* cosx
= __1-cos*squared*x__
cosx

...and now I'm stuck! What went wrong?

2. __cos*squared*x__
cot*squared*x
=___-cos*squared*x__
cos *squared*x
= 1

...and, um, that's it. Thx!!!

2. First, let me make sure I understand the problems.

Is (1) $\displaystyle \sec (-1) + \sec x \sin^2 x$?

Is (2) $\displaystyle \frac{\cos^2 x}{\cot^2 x}$?

3. Hi there!

Um, sort of... 1. sec(-x)-sec(-x)sin*squared*x
2. cos*squared*(-x)
over
cot*squared*x

(sorry, havn't figured out how to get a square in there yet)

What's going on with thoses pesky brackets? How do they work into the equation properly?

THX!!
Laura