Respuesta :

[tex] \frac{ - 3}{5} \\ [/tex]

because , in the third quadrant , the value of cos is negative. Moreover , we can find the third side of the triangle using Pythagoras theorem.

then ,

[tex] \cos(\theta) = \frac{base}{hypotenuse} \\ \\ \dashrightarrow \: \cos(\theta) = \frac{ - 3}{5} [/tex]

hope helpful.

The answer is cos 0 = -3/5

To calculate the answer:

Given :

tan 0 = 4/3 and is in the 3rd quadrant

this implies that both the perpendicular and base are negative.

Perpendicular = -4

Base = -3

Hypotenuse = [tex]\sqrt{(perpendicular)^{2} + (base)^{2} }[/tex]

Hypotenuse = [tex]\sqrt{(-4)^{2} + (-3)^{2} }[/tex]

Hypotenuse = [tex]\sqrt{25} = 5[/tex]

cos 0 = [tex]\frac{Base}{Hypotenuse}[/tex]

cos 0 = -3/5

Therefore, cos 0 = -3/5

To learn more about trigonometric functions refer to :

https://brainly.com/question/25618616

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