Entries from 2022-08-01 to 1 month

Euler’s constant

、 = lim Σ 1/k − lim ln(n) ( n→∞) = − ∞ T.theodor 2022.8.31

circle

任意之 line l ト △ABC ニ於イテ、line l ト line BC、CA、AB ノ交点ヲ D、E、F トシ、□FBCE ガ circle ニ内接スル。 AF/FB・DE/DF・CE/EA = (AF/bFB) 2・BD/DC = (CE/bEA) 2・BD/DC = 1 T.theodor 2022.8.30

circle

任意之 line l ト △ABC ニ於イテ、line l ト line BC、CA、AB ノ交点ヲ D、E、F トシ、□FBCE ガ circle ニ内接スル。 AF/FB・DE/DF・CE/EA = (AF/bFB) 2・BD/DC = (CE/bEA) 2・BD/DC = 1 T.theodor 2022.8.30

derivative

y = axn+bxn-1…+z y' = f(x)'+g(x)'…+y(x)' T.theodor 2022.8.29

function

x2+y2n = r2 T.theodor 2022.8.29

function

√f(x)f(y) = α √( axn+bxn-1…+z )( ayn+byn-1…+z ) = α T.theodor 2022.8.29

function

√f(x)f(y) = 0 √( axn+bxn-1…+z )( ayn+byn-1…+z ) = 0 T.theodor 2022.8.29

function

f(x)f(y) = α ( axn+bxn-1…+z )( ayn+byn-1…+z ) = α T.theodor 2022.8.29

function

f(x)f(y) = 0 ( axn+bxn-1…+z )( ayn+byn-1…+z ) = 0 T.theodor 2022.8.29

Pythagorean triple

Pythagorean triple ( 6/55t, 8/5t,2t ) T.theodor 2022.8.29

Congruent number problem

n = 1/2×a×2 T.theodor 2022.8.29

function

cubic function y = ax3+bx2+cx+d solution 2 a(−b+2√b2−3ac/3a)3+b(−b+2√b2−3ac/3a)2+c(−b+2√b2−3ac/3a)+d = 0 or a(−b−2√b2−3ac/3a)3+b(−b−2√b2−3ac/3a)2+c(−b−2√b2−3ac/3a)+d = 0 T.theodor 2022.8.28

inertia et object

object 固有之 mass ハ、mass ヨリ大キイ外部之力ニヨリ直進シ、mass ニ因リ停止スル。角度を与エラレタ object 、circular motion ハ、中心カラ外ニ向カイ力ガ働ク。 T.theodor 2022.8.28

area of circle

r = a 之 circle カラr = b 之 circle ヲ引イタ時、circle ニ戻セ。 T.theodor 2022.8.28

moment of sphere,cylinder

sphere,cylinder 之 moment ハ、r,l 接触面 1点、l ニ因ル。 T.theodor 2022.8.28

logical fallacy of pendulum's elliptic integral

pendulum ハ、circular motion ナノデ、 elliptic integral トハ、無関係。 T.theodor 2022.8.28

Circular motion

uniform velocity circular motion x(t) = vt θ = 360× vt /π2πr C = 2πr×θ/360 acceleration circular motion v(t) = v0+a0t x(t) = v0t+1/2a0t2 θ = 360× 2v0t+a0t2 /π4πr C = 2πr×θ/360 T.theodor 2022.8.28

function

( x2 + y2 )n = r2n T.theodor 2022.8.27

exponential function

ex = x T.theodor 2022.8.26

area

共通之 area ヲ求メヨ。 T.theodor 2022.8.26

area

共通之 area ヲ求メヨ。 T.theodor 2022.8.26

logical fallacy of Pascal's theorem

六角形 ABCDEF 之 line BC、EF ヲ parallel lines ニ取ル。 T.theodor 2022.8.26

Hyperbola

Hyperbola x<√a2+b2 0°<∠PF2F1<30° x→a ∠PF2F1 → 0° x=√a2+b2 ∠PF2F1 = 90° √a2+b2

circle et ellipse

x2 + y2 = r2 x2/a2 + y2/b2 = 1 (±√r2/2 ,±√r2/2 ) , (±√a2b2/a2+b2 ,±√a2b2/a2+b2 ) T.theodor 2022.8.26

Hyperbola

Hyperbola 接線ガ接点ヲ二ツ持ツ時、二座標ヲ求メヨ。 T.theodor 2022.8.26

function

f(x) = n = 2k lim f(x) = ∞ (x→−∞) lim f(x) = ∞ (x→∞) n = 2k−1 a>0 lim f(x) = −∞ (x→−∞) lim f(x) = ∞ (x→∞) a<0 lim f(x) = ∞ (x→−∞) lim f(x) = −∞ (x→∞) T.theodor 2022.8.26

function

f(x) = number of solutions α≦n T.theodor 2022.8.26 /f(x) =、4/3, 8/5, 16/9

Geometry

triangulum 内之 circle、ellipse、quadrangle ヲ m/n ニ内分スル Geometry 。 T.theodor 2022.8.26

hyperbola

x2/c2 − y2/b2 = 1 T.theodor 2022.8.25

function

x2/a2 + y2/b2 − 1 = 0 x2/ca2 + y2/c2 − 1 = T.theodor 2022.8.25