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If sin(theta+alpha)=a,cos^(2)(theta+beta...

If `sin(theta+alpha)=a,cos^(2)(theta+beta)=b,` then` sin(alpha-beta)=`

A

`ab-(a-a^(2))(1-b^(2))`

B

`ab-sqrt((1-a)^(2)(1-b))`

C

`+-{asqrtb-sqrt((1-a^(2))(1-b))}`

D

`bsqrta-sqrt((1-a)^(2)(1-b))`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the value of \( \sin(\alpha - \beta) \) given that \( \sin(\theta + \alpha) = a \) and \( \cos^2(\theta + \beta) = b \). ### Step-by-Step Solution: 1. **Use the given identities:** We know that: \[ \sin(\theta + \alpha) = a \] and \[ \cos^2(\theta + \beta) = b \] From the second equation, we can express \( \cos(\theta + \beta) \): \[ \cos(\theta + \beta) = \pm \sqrt{b} \] 2. **Express \( \sin(\alpha - \beta) \):** We can use the sine subtraction formula: \[ \sin(\alpha - \beta) = \sin(\alpha)\cos(\beta) - \cos(\alpha)\sin(\beta) \] 3. **Express \( \sin(\alpha) \) and \( \cos(\alpha) \):** From \( \sin(\theta + \alpha) = a \), we can write: \[ \sin(\alpha) = a \cos(\theta) + \cos(\alpha) \sin(\theta) \] We can also find \( \cos(\alpha) \) using the Pythagorean identity: \[ \cos^2(\alpha) = 1 - \sin^2(\alpha) \] 4. **Express \( \sin(\beta) \) and \( \cos(\beta) \):** From \( \cos^2(\theta + \beta) = b \), we can express \( \sin(\beta) \): \[ \sin(\beta) = \sqrt{1 - b} \] And we already have \( \cos(\beta) = \pm \sqrt{b} \). 5. **Substituting back into the sine subtraction formula:** Now we substitute \( \sin(\alpha) \) and \( \cos(\beta) \) into the sine subtraction formula: \[ \sin(\alpha - \beta) = (a \cos(\theta) + \cos(\alpha) \sin(\theta)) \cdot \sqrt{b} - \cos(\alpha) \cdot \sqrt{1 - b} \] 6. **Final expression:** After substituting and simplifying, we can express \( \sin(\alpha - \beta) \) in terms of \( a \) and \( b \): \[ \sin(\alpha - \beta) = a \sqrt{b} - \cos(\alpha) \sqrt{1 - b} \] ### Conclusion: The value of \( \sin(\alpha - \beta) \) can be expressed as: \[ \sin(\alpha - \beta) = a \sqrt{b} - \sqrt{1 - a^2} \sqrt{1 - b} \]

To solve the problem, we need to find the value of \( \sin(\alpha - \beta) \) given that \( \sin(\theta + \alpha) = a \) and \( \cos^2(\theta + \beta) = b \). ### Step-by-Step Solution: 1. **Use the given identities:** We know that: \[ \sin(\theta + \alpha) = a ...
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