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प्रश्न
If `cos B = 3/5 and (A + B) =- 90° ,`find the value of sin A.
उत्तर
We have ,
cos B = `3/5`
⇒ ` cos ( 90° - A ) = 3/5 ( As , A+ B = 90°)`
∴ sin A = `3/5`
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Solution:
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