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In Delta ABC , angle B = 90^(@) find ...

In ` Delta ABC , angle B = 90^(@) ` find the values of :
` sin A cos C + cos A sin C `

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To solve the problem, we need to find the value of \( \sin A \cos C + \cos A \sin C \) in triangle \( ABC \) where \( \angle B = 90^\circ \). ### Step-by-Step Solution: 1. **Identify the Angles**: In triangle \( ABC \), we know that \( \angle B = 90^\circ \). Therefore, the sum of the angles in a triangle gives us: \[ A + B + C = 180^\circ \] Since \( B = 90^\circ \), we can substitute: \[ A + 90^\circ + C = 180^\circ \] 2. **Simplify the Equation**: Rearranging the equation gives us: \[ A + C = 180^\circ - 90^\circ = 90^\circ \] This means that \( A + C = 90^\circ \). 3. **Use the Trigonometric Identity**: The expression we need to evaluate is: \[ \sin A \cos C + \cos A \sin C \] This expression is recognized as the sine addition formula: \[ \sin(A + C) \] 4. **Substitute the Value of \( A + C \)**: Since we found that \( A + C = 90^\circ \), we can substitute this into the sine function: \[ \sin(A + C) = \sin(90^\circ) \] 5. **Evaluate \( \sin(90^\circ) \)**: We know that: \[ \sin(90^\circ) = 1 \] 6. **Final Answer**: Therefore, the value of \( \sin A \cos C + \cos A \sin C \) is: \[ \boxed{1} \]
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