maths.free › Differential Geometry › Curves, arc length and curvature

Curves, arc length and curvature

Parametrised curves, the unit tangent, curvature as the turning rate.

Arc length is ∫|r′(t)| dt; curvature is how fast the unit tangent turns per unit length. A circle of radius R has curvature 1/R. Picture it: the parabola y = x² curving most tightly at its vertex. Think it: curvature and torsion determine a space curve up to rigid motion (the fundamental theorem of curves).

Contoh soal · integrate sqrt(1 + 4x^2) dx from 0 to 1

Integrate sqrt(4x^2 + 1) from 0 to 1

\int_{0}^{1} \sqrt{4 x^{2} + 1}\, dx

Langkah demi langkah

  1. \int_{0}^{1} \sqrt{4 x^{2} + 1}\, dx

    First find an antiderivative F, then evaluate F(b) − F(a).

  2. \int \sqrt{4 x^{2} + 1}\, dx = \frac{x \sqrt{4 x^{2} + 1}}{2} + \frac{\operatorname{asinh}{\left(2 x \right)}}{4}

    SqrtQuadratic rule.

  3. F(1) - F(0) = \left(\frac{\operatorname{asinh}{\left(2 \right)}}{4} + \frac{\sqrt{5}}{2}\right) - \left(0\right)

    Fundamental theorem of calculus: plug in the limits.

  4. = \frac{\operatorname{asinh}{\left(2 \right)}}{4} + \frac{\sqrt{5}}{2} \approx 1.4789

    Simplify.

Tampilkan jawaban
\frac{\operatorname{asinh}{\left(2 \right)}}{4} + \frac{\sqrt{5}}{2}

Sekarang Anda Pilih soal, atau ketik atau gambar soal Anda sendiri. Setiap langkah, sebuah gambar, jawabannya tersembunyi sampai Anda memintanya.

Simpan pekerjaan Anda sendiri

Sebuah akun gratis menambahkan catatan pada setiap pelajaran, catatan apa yang telah Anda selesaikan, masalah yang Anda selesaikan di satu tempat, dan tutor yang dapat Anda tanyakan tentang halaman ini. matematika itu sendiri terbuka untuk semua orang, ditandatangani atau tidak.

Daftar Masuk

Simbol yang digunakan di sini

Sentuh simbol apapun untuk definisi lengkap, gambar, dan apa setiap huruf di dalamnya berarti.

Bagaimana: Curves, arc length and curvature

  1. First find an antiderivative F, then evaluate F(b) − F(a).
  2. SqrtQuadratic rule.
  3. Fundamental theorem of calculus: plug in the limits.
  4. Simplify.

Pertanyaan yang sering diajukan

What is curvature?

For a curve, how fast its direction turns per unit length; for a surface, Gauss's combination of the two principal bendings, and Gauss's theorem says it can be measured from inside the surface without leaving it.

Lainnya di Differential Geometry