# Verify solution of equation

• November 24th 2007, 05:49 PM
overduex
Verify solution of equation
HI!

Directions: verify that the x-values are solutions of the equation.

2cosx-1=0
(a.) x= pi/3

(b.) x= 5pi/3

Thanks again!
• November 24th 2007, 05:57 PM
Macleef
Quote:

Originally Posted by overduex
HI!

Directions: verify that the x-values are solutions of the equation.

2cosx-1=0
(a.) x= pi/3

(b.) x= 5pi/3

Thanks again!

First, convert the radians to degrees
Then, use your calculator to find the decimal values for cosx
For example, in question a)
cos(pi/3) or cos60 = 0.5
Then sub in the value of 0.5 in the equation "2cosx - 1 = 0"
And solve:
2cos(0.5) - 1 = 0
• November 25th 2007, 06:15 AM
topsquark
Quote:

Originally Posted by Macleef
Then, use your calculator to find the decimal values for cosx

Owwch Mommy, my head hurts!! (Crying)

I dearly hope that anyone that would be expected to be able to solve such an equation would already have memorized
$cos(60^o)= \frac{1}{2}$
and not need to rely on a calculator to give them that answer.

-Dan