SOLUTION: can someone help me with the following i'm kind of lost at what to do. thanks!! "Evaluate the following expressions:" a.) {{{cot(-pi/2)}}} b.) {{{sin^2(5pi/6)}}}...(note) that

Algebra.Com
Question 47978: can someone help me with the following i'm kind of lost at what to do. thanks!!
"Evaluate the following expressions:"
a.)
b.) ...(note) that is sin^2
c.) ...(note) that is sec^2
d.) is finding out an angel first of all
i know that i have to use the unit circle but i dont know what to do.
any help would help thanks!!!

Answer by ChillyWiz282(3)   (Show Source): You can put this solution on YOUR website!
1. cot, , , , then
2. has a reference angle of } and in Quadrant 2. sin is negative in Quadrant 2. , so .
Take the square of gives us 1/4
3. has a reference angle of and in Quadrant 4. Sec is positive in Quadrant 4. and then
Squaring it gives
4.


since in both Quadrant 1 and 4, sec(-30degree) is positive

RELATED QUESTIONS

Can someone help me with this problem? I need to evaluate the following expression: (answered by tutorcecilia,butterbean0315)
"solve the following trigonometric eqaution for the given domain (cont.)": can someone... (answered by stanbon)
Can someone help me with this problem? I need to write the following phrase using... (answered by funmath)
Could someone help me with this problem? I need to evaluate the following expression (answered by smartness)
I need to graph the solution set of the following inequalities: x > 4 <... (answered by stanbon)
Can someone please help me with the following question. I am so lost. Thanks Divide... (answered by josmiceli)
Can someone help me on this problem? Evaluate the following expressions: (18 - (answered by checkley71)
Anybody out there who can help with eveluating expressions?? Ineed to evaluate the... (answered by bucky)
Can someone help me with this problem? I need to evaluate the following expression if... (answered by checkley71)