What is the exact value of arccos(sin(x)) and how do we derive it?

The expression arccos(sin(x)) is interesting because it involves the inverse cosine function applied to the sine of x. To find its exact value, we can analyze this step by step:

1. **Understanding the Functions**: The sin(x) function outputs values within the range of -1 to 1. This means we can safely apply the arccos function because arccos is defined for inputs between -1 and 1. The arccos function itself returns an angle in the range of 0 to rac{ an^{-1}(1)}{1} rac{ an^{-1}(1)}{1} (or rac{ rac{ an^{-1}{1}}{1} rac{ an^{-1}{1}}{1} rac{ an^{-1}(1)}{1}}{1}) radians.

2. **Finding the Exact Value**: To express arccos(sin(x)), we first need to consider the relationship between sine and cosine. One key relationship is that:

sin(x) = cos(π/2 – x)

Thus, we can express everything in terms of cos:

arccos(sin(x)) = arccos(cos(π/2 - x))

3. **Applying Inverse Functions**: The property of inverse functions states that:

arccos(cos(θ)) = θ for angles θ in the range of [0, π].

So we need to determine whether (π/2 - x) falls within this range.

4. **Determining Range**: Depending on the value of x:

  • If 0 ≤ x ≤ π/2, then 0 ≤ π/2 - x ≤ π/2. In this case:
  • arccos(sin(x)) = π/2 - x
  • If π/2 < x ≤ π, then 0 < π/2 - x < -π/2 This results in:
  • arccos(sin(x)) = π + (π/2 - x)
  • If x > π, similarly, you would subtract π and adjust accordingly.

5. **Final Expression**: Therefore, we can summarize the results:

  • arccos(sin(x)) = π/2 - x for 0 ≤ x ≤ π/2
  • arccos(sin(x)) = 3π/2 - x for π/2 < x ≤ 3π/2

In conclusion, the exact value of arccos(sin(x)) varies depending on the range of x. Understanding this relationship is essential for solving problems involving trigonometric identities and inverse functions.

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