- #1

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## Homework Statement

x

^{3}-8x+5

## Homework Equations

## The Attempt at a Solution

I am stuck here. I tried factoring.

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- Thread starter trivk96
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- #1

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x

I am stuck here. I tried factoring.

- #2

SammyS

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There's no question here.

What are you trying to do / get to ??

What are you trying to do / get to ??

- #3

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Sorry... solve for x

- #4

Mark44

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You can't solve for x - you don't have an equation.

- #5

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x^{3}-8x+5 is the equation

- #6

Mark44

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This is NOT an equation. An equation ALWAYS has an = in it.x^{3}-8x+5 is the equation

- #7

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Sorry...xThis is NOT an equation. An equation ALWAYS has an = in it.

- #8

Mark44

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OK, finally an equation.

Your polynomial doesn't have any nice (i.e., rational) roots, so short of using a very complicated formula from about the 16th century, it looks to me like you need to get the root or roots by graphing the function or using some approximation technique.

What is the complete problem description?

Your polynomial doesn't have any nice (i.e., rational) roots, so short of using a very complicated formula from about the 16th century, it looks to me like you need to get the root or roots by graphing the function or using some approximation technique.

What is the complete problem description?

Last edited:

- #9

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Sorry about my terrible earlier posts...

The problem asks me to solve x^{3}-8x+5=0 algebraically

heres what i have gotten to so far. Not sure if this will help me:

i made the original equation into x(x-√8)(x+√8)+5=0

The problem asks me to solve x

heres what i have gotten to so far. Not sure if this will help me:

i made the original equation into x(x-√8)(x+√8)+5=0

Last edited:

- #10

gb7nash

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Sorry about my terrible earlier posts...

The problem asks me to solve x^{3}-8x+5=0 algebraically

Did you copy the problem correctly? Are you sure it's not x

- #11

Mark44

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x

Has your teacher shown you a technique for solving cubic equations? If not, you can't be expected to solve this one.

- #12

SammyS

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x^{3}-8x+5=-2

is nicer.

is nicer.

- #13

symbolipoint

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## Homework Statement

x^{3}-8x+5

## Homework Equations

## The Attempt at a Solution

I am stuck here. I tried factoring.

supposed to be, x

What course are you in? What methods and techniques have you studied so far? Do you know how many and what kind of roots this equation should have?

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