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# Maths question watch

1. (Original post by thekidwhogames)
If a quadratic has equal roots thn b^2-4ac=0 is always true e.g. (x-2)^2
If a quadratic has 2 real distinct roots then b^4-4ac>0 and no roots b^2-4ac<0

Think about it. If the thing under the root, the discriminant, is 0 then x=-b+-0/2a --> x=-b/2a (one equal root).

If discriminant > 0 then you have 2 values for the root and hence 2 solutions. If <0, no real root hence no real solutoin.
Ok thanks man appreciate it, so k would be -4 or +4 then?
2. (Original post by peeked)
Ok thanks man appreciate it, so k would be -4 or +4 then?
both
3. (Original post by thekidwhogames)
both
yeah yeah that's what i meant, ok nice! thanks man
4. (Original post by Bananasplitxxx)
Is it k=+-4 then?
Yes, check my previous reply, just edited it.
5. (Original post by Bananasplitxxx)
Attachment 727926
That end part is a pretty massive omission my friend haha

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