angle of elevation 是不是等於 angle of depression ??

angle of elevation 是指你向上看的那一條視線與水平線的角
angle of depression 是指你向下看的那一條視線與水平線的角
a 看 b 的angle of elevation 與 b 看 a 的angle of depression 是一樣的
因為果 2條水平線係 平行 咁果個angle of elevation 和angle of depression 其實是 alt angle(中文好像叫錯角)所以 angle of elevation of a 是等於 angle of depression of b

In a sense, you can say that, dpending on which from which point to which point.

If the point A is at a higher position and B is at a lower position.

angle of elevation from B to A = angle of depression from A to B
because of the ALT angle

Definition of angle of elevation is the angle between the eye level from a
lower poisition to straight line of the the object at the higher position

Definition of angle of depression is the angle between the eye level from a
higher poisition to straight line of the the object at the lower position

Hope this helps.