The cosine of the terminal ray of angle β comes to be -7/√61.
What is the cosine of an angle?
The cosine of an angle is the ratio of the adjacent side to the hypotenuse.
By Pythagoras' theorem
Hypotenuse² = 7²+(2√3)²
Hypotenuse =√61
From the diagram attached
[tex]Cos(180-\beta )=\frac{7}{\sqrt{61} }[/tex]
We know [tex]Cos(180-\beta )=-Cos\beta[/tex]
[tex]-Cos\beta =\frac{7}{\sqrt{61} }[/tex]
[tex]Cos\beta =\frac{-7}{\sqrt{61} }[/tex]
So, the value of cosβ =-7/√61.
Hence, The cosine of the terminal ray of angle β comes to be -7/√61.
To get more about cosine visit:
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