অবতল দাপোণৰ বাবে কাৰ্টেচিয়ান চিহ্ন নিয়ম
অবতল দাপোণৰ বাবে কাৰ্টেচিয়ান চিহ্ন নিয়ম
(along +x-axis) are taken as positive"] F --> H["All distances measured to the left of the origin
(along -x-axis) are taken as negative"] F --> I[The distances measured in the direction
of incident light are positive] F --> J[The distances measured against the direction
of incident light are negative] F --> K[The height above the principal axis
is taken as positive] F --> L[The height below the principal axis
is taken as negative]