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Polynomial functions

Degree, end behaviour, zeros, turning points, and what the graph must look like.

A polynomial of degree n has at most n real zeros and at most n − 1 turning points, and its ends point where the leading term sends them. Factoring finds the zeros; the derivative finds the turning points. Type a polynomial as y = … to see all of it at once.

Isibonelo esisebenza · y = x^3 - 3x

Graph and analyse x^3 - 3x

y = x^{3} - 3 x

Isigaba

  1. x^{3} - 3 x

    An expression in x. Here is what it does.

  2. x \left(x^{2} - 3\right)

    Simplified form.

  3. x = 0, x = - \sqrt{3}, x = \sqrt{3}

    Real zeros (where the graph crosses the axis).

  4. \frac{d}{dx} = 3 x^{2} - 3

    Derivative (slope).

Bonisa impendulo
x \left(x^{2} - 3\right)

Manje Khetha izinkinga, noma ubhale noma udwebe zakho. Isigaba ngasinye, isithombe, impendulo ifihlakele kuze kube ubuza.

Qhubeka usebenza

I-akhawunti emahhala ifaka iziphawulo kulesifundo ngasinye, irekhodi lokuthi yini oqedile, izinkinga zakho ezixazululiwe endaweni eyodwa, nodokotela owaziyo ongabuza mayelana nalekhasi. I-matematics ivulekile kubo bonke, noma ngabe babhalise noma cha.

Bhala Ngena

Amaphawu asetshenziswa lapha

Chofoza noma yiluphi uphawu lwesibonakaliso ukuze uthole ukuchaza okuphelele, isithombe, kanye nokuthi iyiphi inhlamvu ekhona ekhuluma ngaso.

Indlela: Polynomial functions

  1. An expression in x. Here is what it does.
  2. Simplified form.
  3. Real zeros (where the graph crosses the axis).
  4. Derivative (slope).

Imibuzo abantu bebuza

What is a function, really?

A rule that assigns exactly one output to each input. The vertical-line test on a graph is the same idea: no input may have two outputs.

Why do we need complex numbers?

Because x² + 1 = 0 has no real solution, and allowing one new number i with i² = −1 makes every polynomial equation solvable. They then turn out to describe rotation, waves and alternating current more naturally than real numbers do.

Okuningi Precalculus