Math Is Fun Forum

paulb203

Member

Registered: 2023-02-24

Posts: 323

Rearranging formulae

Rearrange;

x^3-3x^2-4=0

to;

x=3+4/(x^2)

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Bob

Administrator

Registered: 2010-06-20

Posts: 10,627

Re: Rearranging formulae

We want /x^2 so factorise on the left and also take the 4 across to the RHS

Divide by x^2 and add 3

Bob

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paulb203

Member

Registered: 2023-02-24

Posts: 323

Re: Rearranging formulae

We want /x^2 so factorise on the left and also take the 4 across to the RHS

Divide by x^2 and add 3

Bob

Thanks, Bob.

That's the way I did it, but MathsGenie did it as follows;

Added 3x^2 to both sides
Added 4 to both sides
Then divided both sides by x^2

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Prioritise. Persevere. No pain, no gain.