Radians Grade 12 Math
What is a Radian?
The radian is a unit of angle measurement, equal to an angle at the center of a circle whose arc is equal in length to the radius.
A circle is 6.28 radians
The Unit Circle and Special Triangles
The unit circle can be used similar to your special triangles. If you look in the first quadrant you will notice that each line creates a triangles with special angles. This unit circle is 6.28 radians.
This background is an example of a special triangle in the unit circle. Although this is a special triangle in the unit circle it has an angle in degrees. Scroll down to learn how to convert degrees into radians.
When calculating your special angles, use radians. Radians is a new unit of measurement taught in grade 12.
1 degree = (π/180) rad
2π rad is equal to 360 degrees. If the student divides both sides by 360 degrees they can find the equation for one degree. Please make sure to simplify like what was done in the example above!
1 rad = (180 degrees/π)
2π rad is equal to 360 degrees. If the student divides both sides by 2π they can find the equation for one radian. Please make sure to simplify like what was done in the example above.
How to Convert π Radians to Degrees?
In order to convert 130 degrees to radians you must.....
This is the method used to convert degrees to radians.
In order to convert 1.2π radians to degrees you must....
This is the method used to convert radians to degrees
Practice
Convert the equations below into radians
A) 145 degrees B) 310 degrees C) 170 degrees D) 290 degrees
Convert the equations below Into radians
A) 4 rad B) 3 rad C) 1.3 rad D) 2.7 rad
Please log on to student.desmos.com and type in the password "sq2x,"to continue your learning on radians!