The OP asks the question here:
after what I thought was a reasonable hint and the OP refused to follow it. The question gets a bounty from a https://math.stackexchange.com/users/42344/juan-santos-atahualpa?tab=bounties&sort=offered, while he asks the same question again, using part of the hint in the answer I gave as a 'partial attempt',
what is the rational behind a question should not be closed if there is an active bounty? In this instance, I think the bounty is ridiculous. This smells like a desperate attempt to get out a homework question.
Indeed, I was guilty of answering a question for bounty, the OP consistently showed no work in many different questions:
I see this is a potential problems...
EDIT: I now actually suspect https://math.stackexchange.com/users/124140/learner is the 2nd account opened by https://math.stackexchange.com/users/42344/juan-santos-atahualpa?tab=bounties&sort=offered, notice how many question asked by the former had a bounty placed by the latter.