SOLUTION: Find the roots of the equation 2X2 - 7X + 4=0 1/σ +1/β & 1/σβ

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Question 476340: Find the roots of the equation 2X2 - 7X + 4=0
1/σ +1/β & 1/σβ
Answer by jorel1380(3719) About Me  (Show Source):
You can put this solution on YOUR website!
2x2-7x+4=
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 2x%5E2%2B-7x%2B4+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%28-7%29%5E2-4%2A2%2A4=17.

Discriminant d=17 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--7%2B-sqrt%28+17+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-7%29%2Bsqrt%28+17+%29%29%2F2%5C2+=+2.78077640640442
x%5B2%5D+=+%28-%28-7%29-sqrt%28+17+%29%29%2F2%5C2+=+0.719223593595585

Quadratic expression 2x%5E2%2B-7x%2B4 can be factored:
2x%5E2%2B-7x%2B4+=+2%28x-2.78077640640442%29%2A%28x-0.719223593595585%29
Again, the answer is: 2.78077640640442, 0.719223593595585. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-7%2Ax%2B4+%29