# exact values

• May 26th 2005, 08:42 PM
kelsey
exact values
what is the exact value of

sin^2(pie/6) - 2sin(pie/6)cos(pie/6) + cos^2(-pie/6)

a. 2- (squareroot)3
b. (2- (squareroot)3)/2
c. (2+ (squareroot)3/2
d. 2+ (squareroot)3
• May 26th 2005, 09:25 PM
MathMan
Please use LaTeX to enter math equations. You can learn how here:

You can also click on the equation that I wrote and see the code I used to generate it.

The above would look like this:

$\displaystyle \sin^2(\frac{\Pi}{2}) - 2\sin(\frac{\Pi}{6}) + \cos^2(\frac{-\Pi}{6})$

a. $\displaystyle 2 - \sqrt {3}$

b. $\displaystyle \frac {2 - \sqrt {3}}{2}$

c. $\displaystyle 2 + \sqrt {3}$
• May 26th 2005, 11:00 PM
paultwang
LaTeX is also case sensitive. Therefore, big $\displaystyle \Pi$ and small $\displaystyle \pi$ mean and display differently.

$\displaystyle \left (\sin(\frac{\pi}{6})\right )^{2}-2\,\sin(\frac{\pi}{6})\cos(\frac{\pi}{6})+ \left (\cos(\frac{\pi}{6})\right )^{2}$
$\displaystyle = \left (\sin(\frac{\pi}{6})-\cos(\frac{\pi}{6})\right )^{2}$
$\displaystyle = 1-\frac{1}{2}\,\sqrt {3}$
• May 27th 2005, 07:27 AM
MathMan
Quote:

Originally Posted by paultwang
LaTeX is also case sensitive. Therefore, big $\displaystyle \Pi$ and small $\displaystyle \pi$ mean and display differently.

Sorry my mistake with the $\displaystyle \pi$
• May 28th 2005, 09:39 AM
kelsey
thanks
but can you help me with the queston now?
• May 29th 2005, 08:25 AM
paultwang
I gave you enough hints.