SOLUTION: Cos^2(x)-5cos(x)+4=0

Question 544049: Cos^2(x)-5cos(x)+4=0
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Cos^2(x)-5cos(x)+4=0
----
Quadratic in cos(x):
Factor:
(cos(x)-4)(cos(x)-1) = 0
------
cos(x) = 4 or cos(x) = 1
----
Only cos(x) = 1 is legitimate
---
x = 0
===============
Cheers,
Stan H.
RELATED QUESTIONS
5cos(x 8.5)�0�2 - 1=0, 0�0�2��x��90�0�2. find... (answered by Alan3354)

Solve 2cos^2 - 5cos(x) +2 =0 for principal values of x. Express the solution(s) in... (answered by stanbon)

5cos^2 theta +cos theta-1=0 Find all possible values of theta in between 0� and... (answered by Fombitz)

Find all the angles between 0� and 360� inclusive which satisfy the equation 4sin^2(x) -... (answered by htmentor)

cos(x+(π/2))-cos(2x)=0 (answered by robertb,Gogonati)

Consider the equation, 5cos(2x)+2=sin(x)-1, where 0 <(or equal) x < 2pi . The number of... (answered by Theo)

Please help me solve this equation (((5cos ^2x+3sinx^-3)))=0,such that 0° (answered by Alan3354)
What are the amplitude and period of... (answered by erica65404)
Find f �(x) if f(x) = 2ln(x) - 5cos(x) + 9 and evaluate f �(2).(Keep 2... (answered by ikleyn)