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Earl Snake-Hips Tucker
11-14-2011, 01:27 PM
I'm pretty sure I never learned this term, if there is one. Anyway. . .

For example:

X2 + x + 1 = 0

The “x squared” component is called the. . . what? Is there a name for the squared, cubed, (and higher powers) components (other than, in this case, the “squared component)?

MikeS
11-14-2011, 01:45 PM
The names I've usually heard are:
x2: Quadratic x3: Cubic x4: Quartic x5: QuinticBeyond this, I've not heard any names in common usage, though that doesn't mean they don't exist.

leahcim
11-14-2011, 01:49 PM
The “x squared” component is called the. . . what? Is there a name for the squared, cubed, (and higher powers) components (other than, in this case, the “squared component)?

Can't go wrong with "the second-order term".

I've been rarely known to refer to x4 as "x tesarracted", but only when I'm being a twit.

John Mace
11-14-2011, 01:50 PM
Also, I would call the example in the OP a "2nd order polynomial". Often, polynomials are used to approximate a function (by expanding that function out as an infinite series). If we were to truncate it to: a +bx, then that would be the "first order approximation", since we only took it out to one power of x. That is what mathematicians and scientist mean when they use that term (1st, 2nd etc order approximation). Sometimes they will used "first order" to mean just an approximation, if they are talking in the vernacular, but if they are being rigorous about things (like in a paper, or a talk to other scientists), they will mean the order of the polynomial expansion they are assuming in their model.

robert_columbia
11-14-2011, 01:58 PM
It's the "quadratic" term. A cubed component is the "cubic" term. Your example equation is known in high schools in the US as a "quadratic equation".

friedo
11-14-2011, 02:00 PM
x3 = cubic term
x = linear term.

Beyond cubic, you could just call it an "nth-order term" where n is the exponent.

Earl Snake-Hips Tucker
11-14-2011, 02:03 PM
OK, thanks all.