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# Algebra query watch

1. Say you have a function X3+X2+X=0. You can't divide through by X to give X2+X+1=0, as you would lose a route. So why is it possible to turn 8X-3/2 = 3/2X1/2 into 8 = (3/2X1/2)(X3/2)?

I'm specifically referring to 11F q3 in C2. A solution can be found here.

Thanks to anyone who can help.
2. (Original post by jpepsred)
Say you have a function X3+X2+X. You can't divide through by X to give X2+X+1, as you would lose a route. So why is it possible to turn 8X-3/2 = 3/2X1/2 into 8 = (3/2X1/2)(X3/2)?

I'm specifically referring to 11F q3 in C2. A solution can be found here.

Thanks to anyone who can help.
If in the first case you cannot divide the function by x it's because your function is not defined to anything for you to divide one side only. But in the second case you modify both sides, thus 8 still equals RHS.
3. My mistake, the first example should have been equal to zero. I'll edit it. I understand why an expression can't be divided through by X, but I still don't understand why one function can be multiplied by X while the other can't.
4. (Original post by jpepsred)
My mistake, the first example should have been equal to zero. I'll edit it. I understand why an expression can't be divided through by X, but I still don't understand why one function can be multiplied by X while the other can't.
No, you still can divide it by zero but then you would have to divide zero by x which wouldn't help you anyway. Also, you must note that your function is zero given some conditions satisfied so dividing through by x would only hold good for the given conditions.

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