Respuesta :

The exact value of cos 7pi/8 is 0. 9988

How to find the value

It is important to note that the value for pi = 3. 142

= cos 7π

Substitute value of π

= cos(7× 3. 142)

= cos 21. 994

Divide 21. 994 by 8

= 2. 740

Let's find the vale of [tex]cos \frac{21. 994}{8}[/tex]

= [tex]cos (2. 749)[/tex]

= [tex]0. 9988[/tex]

Thus, the exact value of cos 7pi/8 is 0. 9988

Learn more about trigonometric identities here:

https://brainly.com/question/7331447

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