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Question
If A + B = 90° and \[\cos B = \frac{3}{5}\] what is the value of sin A?
Solution
We have:
`A+B=90°`
`Cos B=3/5`
`A+B=90°`
⇒ `A=90-B`
⇒`Sin A=sin (90-B)`
⇒` Sin A= Cos B`
⇒ `sin A=3/5 [sin(90°-B)= cos B ]`
Hence the value of sin A is `3/5`
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