Respuesta :

9514 1404 393

Answer:

  15/17

Step-by-step explanation:

cos(arctan(8/15)) = 15/17

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You could assume the ratio values 8 and 15 represent the opposite and adjacent sides of a right triangle. Then the hypotenuse is ...

  h = √(8² +15²) = √289 = 17

The cosine is the ratio of the adjacent side to the hypotenuse, so is ...

  cos(x) = 15/17