Mavzular

⭐ — imtihonda eng ko'p ishlatiladigan formulalar. · 🟢 — masalani tezlashtiradi · 🟡 — ilg'or daraja · 🔵 — chuqur o'rganish (olimpiada darajasi)

Masofa va o'rta nuqta

  • ⭐ Ikki nuqta orasidagi masofa: AB=(x2−x1)2+(y2−y1)2AB = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}
  • ⭐ Kesmaning o'rta nuqtasi: (x1+x22, y1+y22)\left(\dfrac{x_1 + x_2}{2},\ \dfrac{y_1 + y_2}{2}\right)
  • Pifagorning teskari teoremasi: uchburchak tomonlari uchun a2=b2+c2a^2 = b^2 + c^2 bajarilsa, aa qarshisidagi burchak 90°90°.

🟢 Kesmani m:nm : n nisbatda bo'luvchi nuqta

P=(nx1+mx2m+n, ny1+my2m+n)P = \left(\frac{n x_1 + m x_2}{m + n},\ \frac{n y_1 + m y_2}{m + n}\right)

🟢 To'rtburchak turini aniqlash

ShaklTekshiriladigan shart
Parallelogrammdiagonallarning o'rta nuqtalari ustma-ust tushadi
Rombparallelogramm + diagonallar perpendikulyar
To'g'ri to'rtburchakparallelogramm + diagonallar teng
Kvadratparallelogramm + diagonallar teng va perpendikulyar
Trapetsiyabir juft qarama-qarshi tomonlar parallel
  • Parallelogrammning to'rtinchi uchi: D=(xA+xC−xB, yA+yC−yB)D = (x_A + x_C - x_B,\ y_A + y_C - y_B)

🔵 Uchburchakning muhim nuqtalari

NuqtaQanday topiladi
Og'irlik markazi (centroid)G=(x1+x2+x33, y1+y2+y33)G = \left(\dfrac{x_1 + x_2 + x_3}{3},\ \dfrac{y_1 + y_2 + y_3}{3}\right) — medianalar kesishmasi
Tashqi aylana markazitomonlar o'rta perpendikulyarlari kesishmasi
Ortomarkazbalandliklar kesishmasi
Ichki aylana markaziI=(axA+bxB+cxCa+b+c, ayA+byB+cyCa+b+c)I = \left(\dfrac{a x_A + b x_B + c x_C}{a + b + c},\ \dfrac{a y_A + b y_B + c y_C}{a + b + c}\right)

Ichki markaz formulasida a=BCa = BC, b=CAb = CA, c=ABc = AB — qarama-qarshi tomon uzunliklari.