Find the general solution of the equation 2cos(3x)-1=0. Hence find the solutions for -pi < x < pi

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aruv | High School Teacher | (Level 2) Valedictorian

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We wish to slove the problem for x









`x=(2/3)npi+-pi/9`    , n is an integer.

It is general solution of the given problem.

If n=0

`x=+-pi/9 `

If n=1


`x=(7pi)/9 or (5pi)/9`

if n=2


`x=(13pi)/9 or (11pi)/9`  ,it is not in the given interval `(-pi,pi)`


`x=+-pi/9, (7pi)/9,(5pi)/9`