Do you know the discriminant is:
?
You have: a,b and c so you can calculate it directly.
I have a quadratic equation;
3x^2 - 2x +3
I am asked to calaculate the discriminate of the quadratic expression
OK this is a learning curve for me which I don't profess to understand!
I have the above and I think the first step is to find the sum of the two numbers 'a' and 'c', so ac = 9. The sum is b
for this quadratic expression, ac = 3 x 3 = 9 and b = -2
I think I now need to find the factors of 9!
I see 1, 3 and 9
The problem I now see is there is no sum of these to make -2, so I am stuck here at this point?
Anyone know what I am doing wrong?
I might be wrong but it could be referring to a negative solution?
On this example; x^2 + x - 12 = 0
can I use the quadratic formula?
If so is it only the integers on the top line under the square root that should be square rooted, then divide then either add or subract the remaining b?
Yes, you can use the quadratic formula for every quadratic equation.
Now, it can be also important to know why you're calculating the discriminant. Probably you'll lear more about that.
But if you calculate: which can be solved with the quadratic formula, you're calculing the point(s) where the parabola intersects the x-axis, because there , now you can distinguish tree cases:
- , the parabola doesn't intersects the x-axis at all, so there are no intersect points and so no solution.
- , there parabola intersects the x-axis, there are two equal solutions.
- , the parabola intersects the x-axis, there are two different intersect points and so two different solutions.