Can police hide to catch speeders? And if you get ticketed by a police officer that was hiding, do you still have to pay it? Is that entrapment?

The short answer is yes entrapment is illegal but if a police officer is hiding in-between rows of sugar cane and catches you speeding, giving you a ticket is legal and you still have to pay it.

Technically, a police officer running radar in a parked police car invisible from afar is not entrapment.

The definition of entrapment according to Merriam-Webster is, "the action of luring an individual into committing a crime in order to prosecute the person for it."

A police officer hiding in a police car is not luring you to speed. He/she is not tricking you into speeding only to catch you doing it.

So yes police can hide behind bushes to catch you speeding and no you cannot use entrapment as a reason to get out of it.