Cos (x + 6 π) = 4 / 5 why sin (x + 6 π) = 3 / 5

Cos & # 178; (x + 6 / π) + Sin & # 178; (x + 6 / π) = 1sin & # 178; (x + 6 / π) = 1-cos & # 178; (x + 6 / π) = 1 - (4 / 5) & # 178; = 1-25 / 16 = 9 / 25. So: sin (x + 6 / π) = 3 / 5 or sin (x + 6 / π) = 3 / 5 according to the conditions given in the title, such as

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