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will sum and products of quartics be in the hsc? (1 Viewer)

switchpen

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the formula sheet only has the sum and roots of cubics.

my question is whether sum and product equations of quartics and quadratic are needed?
 

SB257426

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i have only seen once in a trial paper they had asked sum of quartics... otherwise i have never seen in my life a quartics q in ext 1.

but i like to know those formulas for quartics... so I think it may be beneficial for u to know.. but not too sure
 

cossine

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the formula sheet only has the sum and roots of cubics.

my question is whether sum and product equations of quartics and quadratic are needed?
Most likely, it will not appear however it isn't that hard to understand.

Try deriving the identity for:

suppose x^4 +a3*x^3 + a2*x^2+ a1*x +a0 = (x-a)(x-b)(x-c)(x-d).

All that is being applied is the distributive law a(b+c).

E.g., Note that for term a3*x^3, x is select three times. This means that each root can only be select once.
Similarly you could do the same thing for a2*x^2 in this case x is selected two times which means you can take the roots two at a time.

It is similar to the idea behind binomial theorem.
 

Trebla

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the formula sheet only has the sum and roots of cubics.

my question is whether sum and product equations of quartics and quadratic are needed?
Definitely. Check the syllabus under Polynomials, there is a dot point that explicitly mentions quartics.

As to why it’s not on the formula sheet, who knows… there are a lot important formulas missing in that sheet that should be on there (not to mention some of the ones already on there are pretty useless).
 

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