Posted by Momo on Wednesday, August 12, 2009 at 5:04pm.
Consider the function y=sqrt(1+cos2x)/2
(everything is under the square root)
a. Can x take on any real value?
b. How large can cos 2x become? How small?
c. How large can 1+cos2x/2 become? How small?
d. What are the domain and range of the original function?

For A, I put that x can be any real value, but the entire function would still be an irrational number.
As for B and C, I'm not exactly sure what values it's asking for. Like, how large or small can the values be without becoming a nonreal number?
And I think I could figure out D if I can figure out B and C. Help?
Thanks!

Math  MathMate, Wednesday, August 12, 2009 at 5:12pm
b. How large can cos 2x become? How small?
You need to supply the range of cos(2x).
c. How large can 1+cos2x/2 become? How small?
Similarly, you need to supply the range of (1+cos(2x))/2
These two questions help you answer #D, as you corrected pointed out.