В чем разница между i don’t care whether or not your car breaks. и I don’t care whether your car breaks. и whether your car breaks or not doesn’t matter. ?Пожалуйста, приведите примеры.

the first sentence does not make sense written fully it would be 'I does not care whether or not your car breaks' this is not proper english.

the second sentence is fine 'I do not care whether your car breaks'

the third sentence is missing an 'it'
' whether your car brakes or not it doesn't matter'

there is a difference between sentace 2 and 3.

in 2 the sentence states your feelings about the car- you don't care about it braking.

in 3 this does not include your feelings about the car but more emphasis on the car itself.
it implies that a) the car either isn't important so if it brakes it doesn't matter
or b) if the car does brake it can be fixed
either way a or b you have no personal opinion about the car.

it's quite difficult to explain I think.... I hope this helps some :)