SOLUTION: Find all values of x in the interval [0, 2π] that satisfy the equation.
16 + 8 cos(2x) = 24 cos(x)
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-> SOLUTION: Find all values of x in the interval [0, 2π] that satisfy the equation.
16 + 8 cos(2x) = 24 cos(x)
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You can put this solution on YOUR website! Find all values of x in the interval [0, 2π] that satisfy the equation.
16 + 8 cos(2x) = 24 cos(x)
divide by 8
2 + cos(2x) = 3 cos(x)
2 + cos^2(x)-sin^2(x) = 3 cos(x)
2 + cos^2(x)-1+cos^2(x) = 3 cos(x)
2cos^2(x)-3cos(x)+1=0
(2cos(x)-1)(cos(x)-1)=0
..
2cosx-1)=0
cosx=1/2
x=π/3 and 5π/3 (quadrants I and IV where cos>0)
or
(cos(x)-1)=0
cosx=1
x=0
(