Find the rectangular coordinates of the point with the polar coordinates ordered pair 7 comma 2 pi divided by 3.

Respuesta :

Answer:

[tex]\left(-\dfrac{7}{2},\dfrac{7\sqrt{3}}{2}\right)[/tex].

Step-by-step explanation:

The given point is

[tex]\left(7,\dfrac{2\pi}{3}\right)[/tex]

We need to find the rectangular coordinates of the given point.

If a polar coordinate is [tex](r,\theta)[/tex], then  

[tex]x=r\cos theta[/tex]

[tex]y=r\sin theta[/tex]

In the given point [tex]\left(7,\dfrac{2\pi}{3}\right)[/tex],

[tex]r=7,\theta=\dfrac{2\pi}{3}[/tex]

Now,

[tex]x=7\cos \dfrac{2\pi}{3}[/tex]

[tex]x=7\cos \left(\pi-\dfrac{\pi}{3}\right)[/tex]

[tex]x=-7\cos \left(\dfrac{\pi}{3}\right)[/tex]

[tex]x=-7\left(\dfrac{1}{2}\right)[/tex]

[tex]x=-\dfrac{7}{2}[/tex]

and,

[tex]y=7\sin \dfrac{2\pi}{3}[/tex]

[tex]y=7\sin \left(\pi-\dfrac{\pi}{3}\right)[/tex]

[tex]y=7\sin \left(\dfrac{\pi}{3}\right)[/tex]

[tex]y=7\left(\dfrac{\sqrt{3}}{2}\right)[/tex]

[tex]y=\dfrac{7\sqrt{3}}{2}[/tex]

Therefore, the required point is [tex]\left(-\dfrac{7}{2},\dfrac{7\sqrt{3}}{2}\right)[/tex].