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Find the value of a in order that f(x)=s...

Find the value of `a` in order that `f(x)=sqrt(3)sinx-cosx-2a x+b` decreases for all real values of `xdot`

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To find the value of \( a \) such that the function \( f(x) = \sqrt{3} \sin x - \cos x - 2ax + b \) is monotonically decreasing for all real values of \( x \), we need to ensure that the derivative \( f'(x) \) is less than zero for all \( x \). ### Step 1: Calculate the derivative \( f'(x) \) The function is given by: \[ f(x) = \sqrt{3} \sin x - \cos x - 2ax + b \] To find \( f'(x) \), we differentiate \( f(x) \): \[ f'(x) = \frac{d}{dx}(\sqrt{3} \sin x) - \frac{d}{dx}(\cos x) - \frac{d}{dx}(2ax) + \frac{d}{dx}(b) \] Using the derivatives of sine and cosine: \[ f'(x) = \sqrt{3} \cos x + \sin x - 2a \] ### Step 2: Set the condition for monotonicity For \( f(x) \) to be monotonically decreasing, we require: \[ f'(x) < 0 \] This implies: \[ \sqrt{3} \cos x + \sin x - 2a < 0 \] Rearranging gives: \[ \sqrt{3} \cos x + \sin x < 2a \] ### Step 3: Analyze the left-hand side The expression \( \sqrt{3} \cos x + \sin x \) can be rewritten using the sine addition formula. We can express it as: \[ \sqrt{3} \cos x + \sin x = 2 \left( \frac{\sqrt{3}}{2} \cos x + \frac{1}{2} \sin x \right) \] This can be recognized as: \[ 2 \sin\left(x + \frac{\pi}{3}\right) \] Thus, we have: \[ \sqrt{3} \cos x + \sin x = 2 \sin\left(x + \frac{\pi}{3}\right) \] ### Step 4: Determine the maximum value The maximum value of \( \sin \) function is 1, hence: \[ \sqrt{3} \cos x + \sin x \leq 2 \] This leads us to: \[ 2 < 2a \] Dividing both sides by 2 gives: \[ 1 < a \] or equivalently: \[ a > 1 \] ### Conclusion Thus, the value of \( a \) must be greater than 1 for the function \( f(x) \) to be monotonically decreasing for all real values of \( x \).

To find the value of \( a \) such that the function \( f(x) = \sqrt{3} \sin x - \cos x - 2ax + b \) is monotonically decreasing for all real values of \( x \), we need to ensure that the derivative \( f'(x) \) is less than zero for all \( x \). ### Step 1: Calculate the derivative \( f'(x) \) The function is given by: \[ f(x) = \sqrt{3} \sin x - \cos x - 2ax + b \] ...
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