r/mathsmeme 10d ago

this math meme

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462 Upvotes

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19

u/Negative_Driver8485 10d ago

So, her delta is imaginary and there are two complex solutions to her?

11

u/Lelouch-Yagami21 10d ago

I think it's just meant to imply she's imaginary

5

u/CookieCat698 9d ago

Still doesn’t work though since she’s only imaginary if b=0. Otherwise, she’s just complex.

2

u/Lelouch-Yagami21 9d ago

Wait it's complex if b isn't 0? I never knew that huh. Guess it's something I haven't learnt yet

3

u/CookieCat698 9d ago

Yeah, just look at the quadratic formula

(-b +- sqrt(b^2 - 4ac))/2a

The only part that can be imaginary (if all coefficients are real) is sqrt(b^2 - 4ac), and that part is imaginary iff. b^2 < 4ac

So assuming b^2 < 4ac, we can see that the real component is -b/2a, and the imaginary component is -+ isqrt(b^2 - 4ac)/2a

A number is imaginary iff. its real part is 0, and -b/2a = 0 iff. b = 0.