maths.free › Precalculus › Parametric equations and polar coordinates

Parametric equations and polar coordinates

Curves traced by a parameter, and the (r, θ) description of the plane.

A parametric curve gives x and y each as functions of t; polar coordinates locate a point by distance r and angle θ. Picture it: the same point (1, 1) is √2 at 45°; the unit circle is simply r = 1. Think it: complex numbers in exponential form are polar coordinates with multiplication built in.

Apdorotas pavyzdys · polar form of 1 + i

Precalculus · Complex-Numbers

Polar form of 1 + I

1 + i

Žingsnis po žingsnio

  1. z = 1 + i = 1 + (1)i

    Read off the real and imaginary parts.

  2. |z| = \sqrt{1^2 + 1^2} = \sqrt{2} \approx 1.4142

    The modulus is the distance from the origin (Pythagoras).

  3. \theta = \arg z = \frac{\pi}{4} \approx 0.78540

    The argument is the angle from the positive real axis (watch the quadrant).

  4. z = \sqrt{2}\left(\cos \frac{\pi}{4} + i\sin \frac{\pi}{4}\right) = \sqrt{2} e^{i \frac{\pi}{4}}

    Polar and exponential forms (Euler).

Atskleisti atsakymą
\sqrt{2} e^{i \frac{\pi}{4}}

Dabar tu Pasirinkite problemą, arba įveskite ar piešti savo. Kiekvienas žingsnis, paveikslas, atsakymas paslėptas, kol jūs klausiate.

Išlaikyti savo darbą

Nemokama paskyra prideda pastabas apie kiekvieną pamoką, įrašą apie tai, ką baigėte, savo išspręstas problemas vienoje vietoje ir mokytoją, kurį galite paklausti apie šį puslapį. Pati matematika yra atvira visiems, kurie yra ar nėra užsiregistravę.

Prisijungti Prisijungti

Čia naudojami simboliai

Bakstelėkite visus simbolius, kad būtų galima apibrėžti visą apibrėžimą, paveikslėlį ir ką reiškia kiekviena raidė.

Kaip vartoti: Parametric equations and polar coordinates

  1. Read off the real and imaginary parts.
  2. The modulus is the distance from the origin (Pythagoras).
  3. The argument is the angle from the positive real axis (watch the quadrant).
  4. Polar and exponential forms (Euler).

Klausimai, kuriuos klausia žmonės

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.

Daugiau informacijos Precalculus

Complex numbersPolynomial functionsRational functionsSequences and seriesThe binomial theoremConic sectionsVectorsExponential and logarithmic functionsPolynomial division and the remainder theorem