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Find exact value in radians
arccos(- square root 3/2)

User Ashleen
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1 Answer

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Answer:

= (6π - πi)/6

Explanation:

We know that the range of arccosine is [0, π]. Since -√3/2 is less than -1, there is no real number x such that cos(x) = -√3/2. Therefore, the equation arccos(-√3/2) has no solution in the real numbers.

However, if we extend the range of the arccosine function to include complex numbers, we can find a solution using the formula:

arccos(z) = π - i ln(z + i√(1-z²))

where ln denotes the natural logarithm.

Substituting z = -√3/2, we get:

arccos(-√3/2) = π - i ln(-√3/2 + i√(1-(-√3/2)²))

Simplifying the expression under the natural logarithm, we get:

arccos(-√3/2) = π - i ln(-√3/2 + i/2)

To evaluate the natural logarithm, we can write -√3/2 + i/2 in polar form:

-√3/2 + i/2 = e^(i(π/6))

Therefore, we have:

arccos(-√3/2) = π - i ln(e^(i(π/6)))

Using the property ln(e^z) = z of the natural logarithm, we can simplify further:

arccos(-√3/2) = π - i (π/6)

Simplifying the expression, we get:

arccos(-√3/2) = (6π - πi)/6

Therefore, the exact value of arccos(-√3/2) in radians is (6π - πi)/6.

I hope this help
User MikeWyatt
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