SOLUTION: Find all solutions of the equation in the interval [0,2π). {{{ 4cos^2(x)=5 - 4 sin(x) }}} Write your answer in radians in terms of π. If there is more than one s

Algebra.Com
Question 985594: Find all solutions of the equation in the interval [0,2π).


Write your answer in radians in terms of π.
If there is more than one solution, separate them with commas.

Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
Find all solutions of the equation in the interval [0,2π).


--------------
Sub 1 - sin^2 for cos^2, then it's a quadratic.
---
4 - 4sin^2 = 5 - 4sin
4sin^2 - 4sin + 1 = 0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation (in our case ) has the following solutons:



For these solutions to exist, the discriminant should not be a negative number.

First, we need to compute the discriminant : .

Discriminant d=0 is zero! That means that there is only one solution: .
Expression can be factored:

Again, the answer is: 0.5, 0.5. Here's your graph:

========================
sin(x) = 1/2
x = pi/6, 5pi/6

RELATED QUESTIONS

Find all solutions of the equation in the interval [0, 2π). 2sinθ-1=0... (answered by ikleyn)
Find all solutions of the equation in the interval [0,2π) sec(θ)+2=0... (answered by lwsshak3)
Find all solutions of the equation in the interval [0, 2pi). -4 cos x =-sin^2(x)+4... (answered by josgarithmetic)
Find all solutions of the equation in the interval [0,2π). {{{2cos^2(x) + 3sin(x) (answered by Alan3354)
Find all solutions of the equation in the interval [0, 2π) sin(x + π/4)... (answered by lwsshak3)
Find all solution of the equation in the interval [0,2pi) 4cos(x) = ((sin^2)(x)) +... (answered by Alan3354,Boreal)
Find all solutions of the equation in the interval [0, 2π). (Enter your answers as a (answered by ikleyn)
Find all solutions to the equation. =2cosθ-√3=0 Write your answer in radians (answered by Alan3354,ikleyn)
Find all solutions of the equation in the interval 0,2π sqrt 3 tan0-1=0 have... (answered by stanbon)