Starting from the formula

We can divide all the angles by 2 and we get

And finally

Angle x is a third quadrant angle, meaning that it is somewhere between 180 and 270. This implies that x/2 lies between 90 and 135. So, x/2 is a second quadrant angle, and its cosine is negative. This means that we can update the previous equation to

You know that

so, plug that value into the expression and you'll get cos(x/2).
Answer:
length of an arc = 1unit
Step-by-step explanation:
given that the circumference of a circle = 6
central angle = 60
length of the arc =?
recall that the circumference of a circle = 2πr
6 = 2πr
r = 6/2π
now to calculate the length of an arc
recall,
length of an arc = 2πr(Ф/360)
length of an arc = 2π(6/2π) × 60/360
length of an arc = 6 × 60/360
length of an arc = 360/360
length of an arc = 1unit
therefore the length of the arc whose circumference is 6 and arc angle is 60° is evaluated to be 1unit
Answer:
y-8=5/6(x-12)
Step-by-step explanation:
y-y1=m(x-x1)
y-8=5/6(x-12)