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-2cos x+square root of 3 = 0

solve the equation for 0 less than or equal to x less than 2 pie

Comments

I'm not sure what the parameters are exactly.
You say <= twice.
Do you mean Solve the equation for x >= 0 and < 2Pi? (for 0 <= x < 2Pi) (or x between 0 and 2Pi)
When you write out math equations in words it becomes ambiguous without punctuation.
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1 Answer

Assuming you mean ( 0 <= x < 2Pi)
 
-2 Cos(x) + √3 = 0
 
-2 Cos(x) = - √3
 
Cos(x) = (-V3)/(-2)  = √3/2
 
Can you get from there to the solution?
 
the possible results are   x = Pi/6 , 11Pi/6

Comments

Sure.
Once you get to
Cos(x) = (-V3)/(-2) = √3/2
you have isolated the variable.   So now you need to find x.
Since taking the cos of x gives √3/2   [that is (√3) / 2 not √(3/2) ]
Then the inverse function will bring √3/2 back to x
    [ function N  = M  then  inverse function M - N ]
Cos(x) = √3/2
Inverse cos √3/2 = arc-cos √3/2 = cos-1 √3/2
 
Find the inverse cos of √3/2 on your calculator.
Then pick the ones that are between 0≤ x < 2 Pi
 
The two answers I gave you ( Pi/6 & 11Pi/6 ) are the exact values solving using maths.
The decimal values you get on your calculator will be approximate values since the calculator needs to round off Pi.
 
BTW - it is pi  not  pie
OOPS - sorry
 
The [ function N = M then inverse function M - N ]
 
should be [ function N = M then inverse function M = N ]