The problem:

http://s13.postimage.org/8rlczwkyv/solve.png

Hi. I was able to find the solution, option D, by plugging the different angles. I'm not sure if this is the best way to solve the problem though. Any ideas?

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- Jul 14th 2012, 11:45 AMFrederickSolving a trigonometric equation
The problem:

http://s13.postimage.org/8rlczwkyv/solve.png

Hi. I was able to find the solution, option D, by plugging the different angles. I'm not sure if this is the best way to solve the problem though. Any ideas? - Jul 14th 2012, 12:00 PMPlatoRe: Solving a trigonometric equation
- Jul 14th 2012, 12:01 PMHallsofIvyRe: Solving a trigonometric equation
First, do you know the basic definitions and trig identities? The very first thing I recommend is writing every thing in terms of sine and cosine, using the definitions of "tangent" and "secant". Then use a trig identity to write a quadratic equation in terms or "cosine" only and, finally, solve the equation.

I see Plato got in just ahead of me and suggested writing it as a quadratic equation in "secant" rather than "cosine"! Much of a muchness. - Jul 14th 2012, 01:13 PMFrederickRe: Solving a trigonometric equation
I tried the quadratic formula way for a different problem but I didn't get the right solution:

http://s14.postimage.org/z6kdxz5n5/problem.jpg

is there a difference between writing it as a quadratic formula in sine or any of the other basic trig definitions? - Jul 14th 2012, 01:31 PMPlatoRe: Solving a trigonometric equation
- Jul 14th 2012, 01:58 PMFrederickRe: Solving a trigonometric equation
I found out that the solution of the last problem I posted can be found by simply factoring. Changing to secant is unnecessary.

- Jul 14th 2012, 02:14 PMPlatoRe: Solving a trigonometric equation
Reply #5 addresses the first post. Besides I even read the attachment in your reply #4!