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Question
If sin A = `9/41` find all the values of cos A and tan A
Solution
We have sin A = `9/41`
As,
`Cos^2 A= 1 − sin^2 A`
=`1-(9/41)^2`
=`1-81/1681`
=`(1681-81)/1681`
`⇒ cos^2 A = 1600/1681`
`⇒ cos A = sqrt(1600/1681)`
`⇒ cos A = 40/41`
Also,
`Tan A = sin A/cos A`
`= ((9/41))/((40/41))`
`=9/40`
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