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Question
If `sin A = 9/41` compute cos ๐ด ๐๐๐ tan ๐ด
Solution
`sin A = 9/41`
`sin A = "๐๐๐๐๐ ๐๐ก๐ ๐ ๐๐๐"/"๐๐๐๐๐๐๐๐ก ๐ ๐๐๐" = 9/41`
Consider the right-angled triangle ABC,
Let x be the adjacent side
By applying Pythagorean
๐ด๐ถ2 = ๐ด๐ต2 + ๐ต๐ถ2
412 = 122 + 92
๐ฅ2 = 412 − 92
๐ฅ = 40
`cos A = "๐๐๐๐๐๐๐๐ก ๐ ๐๐๐"/"โ๐ฆ๐๐๐ก๐๐๐ข๐ ๐" = 40/41`
`tan A = "๐๐๐๐๐ ๐๐ก๐ ๐ ๐๐๐"/"๐ป๐ฆ๐๐๐ก๐๐๐ข๐ ๐ ๐ ๐๐๐" = 9/40`
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