Ntawm no yog cov qauv rau cheeb tsam thiab perimeter ntawm geometric duab ua ke. Nco ntsoov tias lub qauv, uas yog nyob rau hauv cov cheeb tsam grey. Lawv cia li mus rub tshaj nyob rau hauv GeoGebra.
Lub voj voog
A = π • \(r^2\)
Lub circumference(Perimeter) O ntawm ib lub voj voog:
O = 2 • r • π
Areal=π*r^2 Omkreds=2*r*π
Khoom noj qab zib hlais
Lub cheeb tsam Ib tug ntawm ib tug khoom noj qab zib
Ib tug = \(\frac{1}{2}\) • \(r^2\) • \(\theta\)
\(\theta\) nyob rau hauv radians. (saib hloov dua siab tshiab)
Buelængde = r • \(\theta\)
Nyob rau hauv kaum radians
Areal=0.5*r^2*v buelængde= r * v
Kaum nyob rau hauv degrees
Cheeb Tsam = 0.5 * r^2 * (v * π/180) Arc ntev = r * (v * π/180)
Arc ntu
Lub cheeb tsam Ib tug ntawm ntsuab cheeb tsam (lub voj voog Seem):
Ib tug = \(\frac{1}{2}\) • \(r^2\) • (\(\theta\) – nws (\(\theta\))
\(\theta\) nyob rau hauv radians. (saib hloov dua siab tshiab)
Nyob rau hauv kaum radians
Cheeb Tsam = 0.5 * r ^ 2 *(v - nws(v))
Kaum nyob rau hauv degrees
Cheeb Tsam = 0.5 * r ^ 2 *((v * π/180) - nws((v * π/180)))
Annulus
Lub cheeb tsam Ib tug ntawm ntsuab cheeb tsam (annulus):
A = π • ( \(R^2\) – \(r^2\))
Ib = π *(R ^ 2-r ^ 2)
Ellipse
Cheeb tsam Ib tug ntawm ellipse:
A = π • a • b
Circumference O ntawm ellipse:
O = 2 • π • \(\sqrt[]{ \frac{1}{2} \cdot\ (a^2 b^2) } \)
Cheeb Tsam = π * ib * b Omkreds= 2*π*sqrt(0.5*(ib tug ^ 2 b ^ 2))
Rectangle
Ib tug rectangle yog ib tug square, Leej twg 4 cov nplooj ntawv, som er parvis lige store og alle indvendige vinkler er 90 degrees.
Cheeb tsam Ib tug ntawm rectangle
A = l • b (ntev lub sij hawm dav)
Circumference O ntawm rectangle
O = 2 • l + 2 • b
Cheeb Tsam = L * b Omkreds = 2*l + 2*b
Square
Ib tug square yog ib tug square, Leej twg 4 lige store sider og alle indvendige vinkler er 90 degrees.
Ib tug = \(s^2\) (s = sab ntev)
Omkreds O af kvadrat
O = 4 • s
Areal = s^2 Omkreds = 4*s