SOLUTION: Solver the given trig equation exactly on 0<=theta<2pi question is: 2cos(theta/2)= -sqrt2 So far I divided the 2 on the left and the right side of the equation leaving me wit

Question 980560: Solver the given trig equation exactly on 0<=theta<2pi
question is: 2cos(theta/2)= -sqrt2
So far I divided the 2 on the left and the right side of the equation leaving me with, Cos(theta/2)= -sqrt2/2
Now, I'm lost...
(this is a pre-cal question. The topic list is blank for me. Sorry)

Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
Solver the given trig equation exactly on 0<=theta<2pi
question is: 2cos(theta/2)= -sqrt2
So far I divided the 2 on the left and the right side of the equation leaving me with, Cos(theta/2)= -sqrt2/2
------------
Use the double angle formula:
cos(2t) = 2cos^2(t) - 1
= 2*(1/2) - 1
cos(theta) = 0
----
theta = pi/2, 3pi/2

RELATED QUESTIONS
Please help me, I am so lost. The problem is: solve the equation on the interval 0 is... (answered by htmentor)

Solve the equation on the interval 0 < theta < 2pi cos^2 theta-sin^2 theta+sin... (answered by tarungehlot)

I need to solve the equation cos^2(theta) = 4sin(theta)+4, on the interval 0<(theta)<2pi. (answered by jim_thompson5910)

Convert the polar equation r^2=2cos^2(theta) + 3sin^2(theta) into a rectangular equation (answered by robertb)

solve the equation on the interval 0 < or equal to theta < 2pi . 4cos^2 theta =... (answered by solver91311)

Solve each equation on the interval 0 (answered by lwsshak3)
solve the equation on the interval 0 < or equal to theta < 2pi. tan^2 theta = 3/2 sec... (answered by lwsshak3)
I was given the question to find the angles, Sin^2 theta = 2cos theta + 2 So I get... (answered by longjonsilver)
Find the solution(s) on the interval 0 ≤ theta<2(pi) 2cos(theta)+ √3 =... (answered by lwsshak3)