Radians on MCAT?

This forum made possible through the generous support of SDN members, donors, and sponsors. Thank you.
2 Pi radians = 360 degrees.
1 Pi radians = 180 degrees.
etc.

360 degrees is one full 'revolution' of a circle, or one full cycle of sin(x) or cos(x).
180 degrees is one half 'revolution' of a circle, or one half circle of sin(x) or cos(x).
etc.

500px-Sine_cosine_plot.svg.png
 
I saw on AAMC 11 some questions involving radians. Is there some easy way to remember that stuff along with cosine/sin of 0-360 degrees?

yeah if you know what each angle is in radians it's easy to remember what each is equal to. there's only 3 values you need to know, 4 if you wanna include 0.

sin cos
angle: 0 0 1
pi/6 1/2 sqrt(3)/2
pi/4 sqrt(2)/2 same
pi/3 sqrt(3)/2 1/2
pi/2 1 0
 
do me a favor and try not to mention stuff about aamcs for those who haven't taken them. Thanks.
 
Radians are easy.

Picture an angle whose vertex is in the center of a circle. An angle of one radian is one with rays subtending an arc equal in length to the radius. That's the basis of the measurement, the equivalence of the arc length for such an angle with the radius.

2pi radians measures an angle that goes all the way around. This follows from the fact that the circumference of the circle is 2 pi r. The conversion factor is 2 pi radians per cycle.
 
Top