SOLUTION: Solve equation: (x+1/x-1) + (2/x)= (x/x+1) How do I solve this?

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Question 202332: Solve equation:
(x+1/x-1) + (2/x)= (x/x+1)
How do I solve this?

Answer by dyakobovitch(40) About Me  (Show Source):
You can put this solution on YOUR website!
For the equation, (x+1/x-1) + (2/x)= (x/x+1), your first step is to eliminate your denominator. This can be done by looking for the least common multiple of x, (x-1), and (x+1), which happens to be x(x-1)(x+1).
As such, you want to multiply all three parts of your equation by x(x-1)(x+1). This multiplication preserves the equality of the equation. Your result is x(x-1)(x+1)(x+1)/(x-1) + 2x(x-1)(x+1)/x= x^2(x-1)(x+1)/(x+1), which simplifies to x(x+1)^2 + 2(x-1)(x+1)= x^2(x-1).
Simplifying the quadratic equation, you get x^3+2x^2+x +2x^2-2=x^3-x^2. Your new quadratic equation becomes 5x^2+x-2=0.
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 5x%5E2%2B1x%2B-2+=+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=%281%29%5E2-4%2A5%2A-2=41.

Discriminant d=41 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-1%2B-sqrt%28+41+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%281%29%2Bsqrt%28+41+%29%29%2F2%5C5+=+0.540312423743285
x%5B2%5D+=+%28-%281%29-sqrt%28+41+%29%29%2F2%5C5+=+-0.740312423743285

Quadratic expression 5x%5E2%2B1x%2B-2 can be factored:
5x%5E2%2B1x%2B-2+=+5%28x-0.540312423743285%29%2A%28x--0.740312423743285%29
Again, the answer is: 0.540312423743285, -0.740312423743285. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+5%2Ax%5E2%2B1%2Ax%2B-2+%29
.