Question 532232: -2sin(t)+2cos(2t)=0
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! -2sin(t)+2cos(2t)=0
--------
-2sin(t) + 2*(cos^2 - sin^2) = 0
---
-2sin(t) +2(1-2sin^2) = 0
---
-2sin(t) + 2 - 4sin^2 = 0
---
4sin^2 + 2sin -2 = 0
---
2sin^2 + sin - 1 = 0
---
(2sin-1)(sin+1) = 0
----
2sin = 1 or sin = -1
----
sin = 1/2 or sin = -1
t = pi/6 or (5/6)pi or (3/2)pi
===================================
Cheers,
Stan H.
===============
|
|
|
