+0  
 
0
2
1
avatar+746 

Degrees are not the only units we use to measure angles.  We also use radians.  Just as there are $360^\circ$ in a circle, there are $2\pi$ radians in a circle. Compute $\cos \frac{2 \pi}{7},$ where the angle $\frac{2 \pi}{7}$ is in radians.

 Jan 11, 2024
 #1
avatar+36899 
+1

2 pi /7  R   =    2pi / 7   R *  360°/2pi R   = 51 3/7 °   

 

cos (2pi/7 R) = .6234898     ( Using calculator in RADIAN mode) 

cos (51 /37 °) = .6234898    ( using calculator in DEGREE mode) 

 

   YOUR calculator may have a different way of calculating in RADIAN or DEGREE mode, but the WEB2.0 calculator is switched between the two modes by checking one of the two buttons in the lower left corner ....

 Jan 11, 2024

1 Online Users