Verified answer

There are no solutions in the interval 0° < e < 360°

cos(0) = cos(360) = 1, but 0 and 360 are not in interval.

If you were to change the interval to 0° ≤ e ≤ 360°, then solutions would be:

e = 0°, 360°

Mαthmφm

cos e = 1

e = cos^-1 1

= 0* or 360*

but for 0°<e<360° , the answer is { } , the empty set = no solutions exist

for me, converting to radians is easier, meaning between 0 and 2pi. then i draw the cos graph and find that cos = 1 at 0 and 2pi, or 0 and 360 degrees.