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Solve the equation in the interval [0,2π]. If there is more than one solution write them separated by commas. (cos(x))^2= 1/16x=

User Kirstine
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1 Answer

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The solutions to the equation
$\cos^2(x) = (1)/(16)$ in the interval
$[0, 2\pi]$ are:


$x \approx 1.318, 1.823, 4.460, 5.965$

To solve the equation
$\cos^2(x) = (1)/(16)$ in the interval
$[0, 2\pi]$, we can take the square root of both sides to get rid of the squared term.


$√(\cos^2(x)) = \sqrt{(1)/(16)}$

Since
$\cos(x)$ is always positive or zero, we can simplify the equation to:


$\cos(x) = \pm(1)/(4)$

To find the solutions in the interval
$[0, 2\pi]$, we need to consider the values of
$x$ for which
$\cos(x)$ is equal to
$\pm(1)/(4)$.

Using the unit circle or a calculator, we can find the angles where
$\cos(x)$ is equal to
$(1)/(4)$ or
$-(1)/(4)$.

For
$\cos(x) = (1)/(4)$, the solutions in the interval
$[0, 2\pi]$ are approximately:


$x \approx 1.318, 5.965$

For
$\cos(x) = -(1)/(4)$, the solutions in the interval
$[0, 2\pi]$ are approximately:


$x \approx 1.823, 4.460$

User Damote
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