SOLUTION: Solve sqrt(2) cos(x) +1=0 for 0 <= x < 2pi

Algebra ->  Trigonometry-basics -> SOLUTION: Solve sqrt(2) cos(x) +1=0 for 0 <= x < 2pi      Log On


   

Question 1033305: Solve sqrt(2) cos(x) +1=0 for 0 <= x < 2pi
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve sqrt(2) cos(x) +1=0 for 0 <= x < 2pi
---------
cos(x) = -1/sqrt(2)
----
Reference angle:: pi/4
-----
Since cos is negative in QIII and QIV,
x = (3/4)pi or x = (5/4)pi
--------------
cheers,
Stan H.
------------