Question

Solve the inequality: 2x2 - x + 3 ≥ 0.
A. x ≤ -2 or x ≥ 3
B. -2 ≤ x ≤ 3
C. No solution
D. All real numbers

Answer 1

set that thing equal to zero first, then solve for \(x\) you should get two answers

Answer 2

i use the quad formila and got .95 and 1.45

Answer 3

yeah i did that

Answer 4

Would that be all reall #?

Answer 5

@satellite73

Answer 6

@zepdrix

Answer 7

You can factor that if I'm not mistaken.

Answer 8

BTw thats 2x^2

Answer 9

Oh, Zep is here, hooray!

Answer 10

Hmm looks like it doesn't factor :( darn..

You threw it into the `Quadratic Formula` ?
What do you get for the part under the square root? :o

Answer 11

\[\Large x=\frac{1\pm\sqrt{1^2-4(2)(3)}}{2(2)}\]Something like that? :o

Answer 12

yes

Answer 13

Hmmmm looks like we get a negative under the root, yes?
Which means no `real` solutions exist.

Answer 14

Err hmm.. that didn't work out correctly lol

this function is always above the x-axis, so it doesn't have any roots.
but we don't care about roots, so maybe we shouldn't use the quadratic formula :D lol

Answer 15

since the discriminant is negative, there are no real zeros
since it opens up, that means it lies entirely above the \(x\) axis
that means it is always positive
they are synonyms

Answer 16

ya there we go XD that's a good way to explain it!
always positive or always negative since no roots.
always positive in this case since the coefficient on the leading term (highest power of x) is positive.

Answer 17

OHHHH ok :D

Answer 18

Thanks guys

Answer 19

zep can you show me a example of what would be all reall numbers for a awnser?

Answer 20

this one is `all real numbers` broski :o
did i confuse you?

Answer 21

ohh man i did

Answer 22

Here is what the function looks like.
https://www.desmos.com/calculator/oqbflo3xvr

They're asking, for what x values is the function positive?

Answer 23

yes it is