Answer:
![\cos (115\degree)=-0.423](https://tex.z-dn.net/?f=%5Ccos%20%28115%5Cdegree%29%3D-0.423)
Step-by-step explanation:
The parametric equations of a circle is
and ![y=r\sin \theta](https://tex.z-dn.net/?f=y%3Dr%5Csin%20%5Ctheta)
The radius of the unit circle is 1 unit.
This implies that any point on the unit circle is represented by:
and ![y=\sin \theta](https://tex.z-dn.net/?f=y%3D%5Csin%20%5Ctheta)
where
is the angle in standard position,
From the question, the given angle in standard position is
.
This angle intersects the unit circle at ![x=-0.423](https://tex.z-dn.net/?f=x%3D-0.423)
But ![x=\cos \theta](https://tex.z-dn.net/?f=x%3D%5Ccos%20%5Ctheta)
We substitute
and ![x=-0.423](https://tex.z-dn.net/?f=x%3D-0.423)
This implies that: ![\cos (115\degree)=-0.423](https://tex.z-dn.net/?f=%5Ccos%20%28115%5Cdegree%29%3D-0.423)
Exponent rule : a^-b = 1 / a^b
52^-5 =
1 / 52^5 =
1 / (52 * 52 * 52 * 52 * 52)
What is it maybe i can help?
Answer:
Hey there!
4a^2-20a+25 can be factored to (2a-5)(2a-5). Thus, the side length of the square is 2a-5. Basically, we want to find two of the same binomials that can multiply to get 4a^2-20a+25. For example, 2a times 2a = 4a^2, and you can use the foil method to solve for the rest.
4a^2 - 20a +25
(2a)^2 - 20a + (-5)^2
(2a - 5)^2
(9a2 − 16b2) is just a difference of squares, and can be factored to (3a+4b) and (3a-4b). The difference of squares formula can give us this.
Let me know if this helps :)