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