# trig equation

• Mar 26th 2006, 02:34 PM
c_323_h
trig equation
solve the trig equation sec(x)-2=0 for exact solutions in the interval
0<= x <= 2pi
• Mar 26th 2006, 03:39 PM
topsquark
Quote:

Originally Posted by c_323_h
solve the trig equation sec(x)-2=0 for exact solutions in the interval
0<= x <= 2pi

sec(x)=2

Now, sec=1/cos

Thus cos(x)=1/2.

So for what values of x is cos(x)=1/2?

-Dan
• Mar 26th 2006, 03:39 PM
ThePerfectHacker
Quote:

Originally Posted by c_323_h
solve the trig equation sec(x)-2=0 for exact solutions in the interval
0<= x <= 2pi

That means,
$\sec x=2$
because secant is reciprocal function of cosine we have,
$\cos x=\frac{1}{2}$ for $0
Thus,
$x=\frac{\pi}{6},\frac{11\pi}{6}$
• Mar 26th 2006, 03:45 PM
c_323_h
i've got pi/3 and 5pi/3
• Mar 26th 2006, 04:17 PM
topsquark
Quote:

Originally Posted by c_323_h
i've got pi/3 and 5pi/3

Yup. ThePerfectHacker isn't having a good day with trig. I hope he's okay... :)

-Dan
• Mar 26th 2006, 04:22 PM
ThePerfectHacker
Quote:

Originally Posted by topsquark
Yup. ThePerfectHacker isn't having a good day with trig. I hope he's okay... :)

-Dan

No I am so tired now. Not really realizing what I am doing.
If I make another mistake I am leaving this site for today.
• Mar 26th 2006, 04:26 PM
topsquark
Quote:

Originally Posted by ThePerfectHacker
No I am so tired now. Not really realizing what I am doing.
If I make another mistake I am leaving this site for today.

It's okay. We still love you. Get some sleep for me!

-Dan