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Answer:

Step-by-step explanation:

hello :

the coordinates of the point on the unit circle at the given angle.-225°:

x= cos(-225°)= -√2/2

y = sin (-225°)= √2/2

The coordinates of the point on the unit circle at an angle -225°° are [tex](\frac{-\sqrt{2} }{2} , \frac{\sqrt{2}} {2} )[/tex].

What are coordinates of the point?

" The coordinates of the point is defined as the pair of such points which represents the exact location of the point."

What is unit circle?

" Unit circle means a circle with radius equals to 1unit."

Formula used

Equation of the circle with center (0, 0) and radius r

[tex]x^{2} +y^{2} =r^{2}[/tex]

Coordinates of the point on the circle (rcosθ , rsinθ)

cos(-θ) = cosθ

sin (-θ) = -sinθ

cos ([tex]\frac{3\pi }{2}[/tex] -θ) = -cosθ

sin ([tex]\frac{3\pi }{2}[/tex] -θ) = -sinθ

According to the question,

Given θ = -225°

Unit circle 'r' = 1

Therefore Coordinates are,

'x' coordinates represented by  rcosθ

'y' coordinates represented by  rsinθ

Substitute the value of r and θ in the coordinates of the point we get,

x = rcosθ

 = 1 × cos (-225°)

 = cos (225°)

 = cos ( 270° - 45°)

 [tex]=cos(\frac{3\pi }{2} -\frac{\pi }{4} )[/tex]                      

[tex]= - sin(\frac{\pi }{4}) \\= - \frac{1}{\sqrt{2} } \\=-\frac{\sqrt{2} }{2}[/tex]

y = rsinθ

 = 1 × sin (-225°)

 = -sin (225°)

 = -sin ( 270° - 45°)

 [tex]=-sin(\frac{3\pi }{2} -\frac{\pi }{4} )[/tex]                      

[tex]= -( - cos(\frac{\pi }{4})) \\= \frac{1}{\sqrt{2} } \\=\frac{\sqrt{2} }{2}[/tex]

Hence, coordinates of the point on the unit circle at an angle -225°° are [tex](\frac{-\sqrt{2} }{2} , \frac{\sqrt{2}} {2} )[/tex].

Learn more about coordinates of the point here

https://brainly.com/question/16679833

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