Question 1125345
<font face="Times New Roman" size="+2">


You think correctly.


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \frac{2\,\sqrt{42}\ -\ 2}{15}]


is not the correct answer.


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ -\(\frac{2\,\sqrt{42}\ -\ 2}{15}\)\ =\ \frac{2\ -\ 2\,\sqrt{42}}{15}]


is the correct answer.  Your arithmetic was good, but somewhere you made an error with your signs.  Double check your work.  Remember that the cosine is positive in the 1st and 4th quadrants, and the sine is positive in the 1st and 2nd quadrants.
								
								
John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
<img src="http://c0rk.blogs.com/gr0undzer0/darwin-fish.jpg">
*[tex \Large \ \
*[tex \LARGE \ \ \ \ \ \ \ \ \ \  
								
{{n}\choose{r}}
</font>