Cos 157.5º=-cos (180º-157.5º)=-cos 22.5=-cos(45/2)
cos Ф/2=⁺₋√((1+cosФ)/2).
In this case 157.5º is in the second quadrant, therefore we use the following equation:
cos Ф/2=-√((1+cosФ)/2). (we will have a negative number)
cos 157.5º=-cos (45/2)=-√((1+cos 45º)/2)
=-√((1+√2/2)/2)
=-√((2+√2)/4)
=-√(2+√2) / 2 (≈-0.92387...)
Answer: cos 157.5º= -√(2+√2) / 2
Answer:
<h3>
a. the vertex represents a minimum point</h3><h3>
b. f(x) = (x + 5)² - 5</h3>
Step-by-step explanation:
a.
a = 1 > 0 ← that means the parabola opens up, so the vertex is minimum of the function
b.

Answer: (1/3,2)
Step-by-step explanation:
Let O(x,y) be the circumference of the triangle PQR,
Thus, by the property of circumcenter all the vertices of the triangle are at same distance from this circumcenter.
Thus, PO = QO
By the distance formula,





---------(1)
Similarly, QO = RO





------------(2)
By adding equation (1) and (2),
24 x = - 8
x = 1/3
By putting this value in equation (1),
We get,
Thus, 4 - 8 y = -12
8 y = 16
y = 2
Answer:
The equation for the relationship is
.
Step-by-step explanation:
Given that point
is part of a direct relationship. That is:

(1)
Where
is the proportionality constant.
If we know that
and
, then the proportionality constant is:



Lastly, the equation for the relationship is
.