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In this picture the measure of angle theta is 1 radian

In this picture the measure of angle theta is 1 radian-example-1

2 Answers

5 votes

Answer:

True.

Explanation:


User LordMarty
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To solve this, we are going to use the formula for the area of the sector of a circle:
A= (1)/(2) r^2 \alpha
where

A is the area of the circular sector.

r is the radius of the circle.

\alpha is the central angle in radians.

We know form our problem that that the measure of the central angle is 1 radian, so
\alpha =1. We can also infer from the picture that the radius of the circle is 3in, so
r=3in. Lets replace those values in our formula to find
A:

A= (1)/(2) r^2 \alpha

A= (1)/(2) (3in)^2(1)

A=4.5in^2

We can conclude that the area of the circular sector in the picture is 4.5 square inches.

To prove that the arc length is indeed 3 inches, we are going to use the formula:
A_(L)=r \alpha
where

A_(L) is the arc length.

r us the radius of the circle.

\alpha is the central angle.

We know from our problem that
r=3in, and
\alpha =1, so lets replace those values in our formula:

A_(L)=r \alpha

A_(L)=(3in) \alpha

A_(L)=3in

We can conclude that the length of the arc is indeed 3 inches.
User Karen White
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8.9k points