Answer:
The formula for number of images formed by two plane mirrors placed at certain angle is (360/n). n is the angle.
just remember that the number of images formed must be ODD numbers.
if the result is even then you need to subtract 1 from that.
if it is odd u need not subtract , since the number of images ever formed are only odd.
using the formula 360/n where n is the angle
for 180 degrees
360/180 = 2 - 1 = 1 images
for 120 degrees
360/120 = 3 images
for 90 degrees
360/90 = 4-1 = 3 images
for 60 degrees
360/60 = 6 - 1 = 5 images
45 degrees
360/45 = 8 - 1 = 7 images
