+0  
 
0
207
1
avatar

sin^2(x) + cos(x) + 1 = 0 In the interval [0, 2π)

Guest Jun 1, 2017
 #1
avatar+93356 
+1

sin^2(x) + cos(x) + 1 = 0 In the interval [0, 2π)

 

\(sin^2(x) + cos(x) + 1 = 0 \\ -cos^2(x) + cos(x) + 2= 0\\ cos^2(x) - cos(x) - 2= 0\\ let\;\;t=cos(x)\\ t^2-t-2=0\\ (t-2)(t+1)=0\\ t=2\;\;or\;\;t=-1\\ -1\le t \le 1\\ so\;\; t=-1\\ cos(x)=-1\\ x=\pi \)

Melody  Jun 1, 2017

42 Online Users

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.