Is this root real?
x 2 + 2 x + 1 0
How many real roots does the polynomial above have?
Check out my latest note if you are interested in differentiation of weird but wonderful functions
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3 solutions
Yeah. Same way. I don't know why is this problem so hard for 6% of people.
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who knows. hopefully the solutions will help them be able to in the future!
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Δ = 2 2 − 4 × 1 × 1 0 = − 3 6
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@A Former Brilliant Member – shoot! You didn't see that.. xd
Apparently it's now hard for 9% of people.
Imagine being that 9% that can't do 10th grade basic australian math.
I forgot the roots had to be real
Though x = 3i - 1 can be one of the non-real roots, seeing as there aren't any real roots.
Consider the roots of
x 2 + 2 x + 1 0 x 2 + 2 x + 1 ( x + 1 ) 2 = 0 = − 9 = − 9
As the left-hand side ( x + 1 ) 2 ≥ 0 for all real x , there is 0 real root to the equation.
No real roots since b 2 < 4 a c
We can check is this equation has real roots by evaluating the discriminant : Δ = 2 2 − 4 ( 1 ) ( 1 0 ) = − 3 6
Since − 3 6 < 0 , there are no real roots