Solve for X and Find P(-2) | Helpful Homework Solutions

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Homework Help Overview

The discussion revolves around solving quadratic equations and evaluating a polynomial function. The original poster presents several equations to solve for x and a polynomial P(x) for which they need to find P(-2).

Discussion Character

  • Mixed

Approaches and Questions Raised

  • Participants discuss the use of the quadratic formula for the first two equations and question the original poster's calculations. There is also a focus on clarifying the expression in the third equation due to potential ambiguity in its notation.

Discussion Status

Some participants have provided guidance on using the quadratic formula and substituting values into the polynomial. There is an ongoing exploration of the calculations, with participants noting discrepancies in the results and seeking clarification on the equations presented.

Contextual Notes

There is mention of potential errors in the original poster's calculations, particularly regarding signs and the interpretation of the third equation. Participants are encouraged to share their work for further assistance.

Sope0nARope
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i'm havin trouble with a few problems on my homework so help would be much appriciated

solve for x:

1) 3x^2 - 2x +1=0

2) x^2 -4x + 20 = 0

3) (-2/x+1) + (3/1-x) = 7/x^2-1

and
find p(-2) if P(x) = 2x^4 - x^3 + 4x^2 + -8x + 3

again thanks for any help :)
 
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Look up the quadratic formula for the first three.

For the last one, substitute -2 in everywhere you see x, multiply and add them together.

If you post an attempt, we can help you a bit more.
 
i didnt think of using the quadratic formula i tried it but it still doesn't seem right i got
x=2/3 + or - i root60/6 for the 1st 1

and x = 6,-2 for the 2nd i must be doing something wrong
 
I've got complex answers for both of the first two as well, but they don't match your results. Probably missed a '-' sign somewhere.

For the third one, it looks like your parenthesis are a bit ambiguous.

(-2/x+1)

Is this (-2/x) +1 or -2/(x+1)?

Can you post your work, and we'll find the errors?
 

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