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CS Inequality

Sorry if I am being stupid and please point out what i am missing
Original post by Iconic_panda
Sorry if I am being stupid and please point out what i am missing


You're currently missing the question from your original post.

SS
i get everything except the part it is saying b^2 has to be less or equal to 4ac, why does the discriminant has to be non positive?
(edited 5 years ago)
Screen Shot 2018-10-22 at 16.31.41.png72.5KB
yeah sorry i was typing up my question
Original post by Supersaps
You're currently missing the question from your original post.

SS
Original post by Iconic_panda
i get everything except the part it is saying b^2 has to be less or equal to 4ac, why does the discriminant has to be non positive?


Look at the expression right after saying 0<=

That is a quadratic that is either =0 or greater than 0. It is never negative.

Think about a quadratic when it dips into the negatives, that means it has two distinct roots.

Here we don’t have that case, so we either have only one root, or no roots.

Hence the discriminant is <= 0
(edited 5 years ago)
ohhh sorry my mistake yeah that wasn't that complicated thanks!
Original post by RDKGames
Look at the expression right after saying 0<=

That is a quadratic that is either =0 or greater than 0. It is never negative.

Think about a quadratic when it dips into the negatives, that means it has two distinct roots.

Here we don’t have that case, so we either have only one root, or no roots.

Hence the discriminant is <= 0

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