Angles can be measured in units called radians. One radian is the measure of an angle that subtends an arc whose length is equal to the radius of the circle. By this definition, which statement is NOT true?
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Step-by-step explanation:
The first one is true.
[tex]2\pi = 360[/tex]
We can see this by converting the problem from radian to degree
[tex]2\pi * (\frac{180}{\pi} = 360^\cric )[/tex]
The second one is true.
[tex]\pi * (\frac{180}{\pi} = 180^\cric )[/tex]
There is 180 degrees in a semi / half circle
(Answer) The third one is not true.
[tex]2\pi r * y[/tex] does not equal the arc
The length of an arc equals
[tex]s = r\theta[/tex]
s = length
r = radius
[tex]\theta = angle\ in\ radians[/tex]
Answer:
The length of an arc subtended by a central angle of x radians is 2πr • x.
Step-by-step explanation:
I got it right.