I did have a look at the sticky but I'm still confused.
3x^2 + x - 2 > 0
I got
x > 2/3 and x > -1
For the interval notation I got
(-1, infinity) union (2/3, infinity)
But the answer is:
(negative infinity, -1) union (2/3, infinity)
Why is that? :S
Hello, Klutz!
You had: .
You factored and got: .
We have the product of two factors and it's suppose to be positive.
. . Under what conditions is this true?
Obviously, if both factors are positive, their product is positive.
. . (You saw this one.) **
Also, if both factors are negative, their product is positive.
. . (You missed this one!)
We have: .
These can be condensed into: .
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
**
You had: .
Can you see that this is redundant?
You want numbers greater than and greater than
Any number greater than satisfies both inequalities.
They can be condensed: .
The answer is: .