course relative to bearing help ?

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hi hunters

could someone please explain 'course relative to bearing'

if a ship is spotted at 301 degrees, what is the bearing relative to me ?

im watching olc's tutorial and trying to understand the bit where he is plotting the course of the ship, and, he says its 59 degrees relative to his course.

ive treid to work this out on my own and it doesnt add up, coz i know something happens when a ship is moving away from, like, subtracting the 301 from 360 which gives 59. and yet this doent always seem to work.

ive tried it with numerous different courses and i can not get the maths to work - and i have to say its driving me nuts: is there a formula for this ?

ie; when a ship is coming to me and when a ship is moving away.
im very confused...

thanks