Canucker

Hopefully there is someone around here who is better at math than I am (which, I admit, is not difficult to be, even in less intelligent circles).
I have two types of questions that I hope you can help me solve and maybe briefly explain why. This is not just to get answers out of you guys, because I have the answers in front of me. I just don't get why.

1) Determine the exact value of tan(5pi/6)
2) Solve: cscx + 2 = 0 (in radian mode)

I'm soo lost guys, please help...

jenkster

1. You should just remember these stuff. Reference angle is pi/6, so it's either positive or negative sqrt(3)/3. In this case, angle is in 2nd quadrant, so answer is -sqrt(3)/3.

Another way you can do is is by: tan = sin/cos
sin(5pi/6) = 1/2
cos(5pi/6) = -sqrt(3)/2
sin/cos = -1/sqrt(3) = -sqrt(3)/3

2. move 2 to other side to get cscx = -2
take reciprocal of each side to get sinx = -1/2
now you know x = 7pi/6 or 11pi/6
if you want all solutions, then x = 7pi/6 + 2pik or 11pi/6 + 2pik where k is an integer.

Hope this helped.

andreaaaaaa

yeah, you really have to know the unit circle.