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If sin A = `9/41` find all the values of cos A and tan A

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#### 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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