x^2+x+2=0 eching

$$x ^ { 2 } + x + 2 = 0$$

x uchun yechish (complex solution)

$$x=\frac{-1+\sqrt{7}i}{2}\approx -0,5+1,322875656i$$

$$x=\frac{-\sqrt{7}i-1}{2}\approx -0,5-1,322875656i$$

Kvadrat tenglamalaridan foydalanish qoidalari

ax^{2}+bx+c=0 shaklidagi barcha tenglamalarni kvadrat formulasi bilan yechish mumkin: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. Kvadrat formula ikki yechmni taqdim qiladi, biri ± qo'shish bo'lganda, va ikkinchisi ayiruv bo'lganda.

$$x^{2}+x+2=0$$

Ushbu tenglama standart shaklidadir: ax^{2}+bx+c=0. Kvadrat tenglama formulasida, \frac{-b±\sqrt{b^{2}-4ac}}{2a} 1 ni a, 1 ni b va 2 ni c bilan almashtiring.

$$x=\frac{-1±\sqrt{1^{2}-4\times 2}}{2}$$

1 kvadratini chiqarish.

$$x=\frac{-1±\sqrt{1-4\times 2}}{2}$$

-4 ni 2 marotabaga ko'paytirish.

$$x=\frac{-1±\sqrt{1-8}}{2}$$

1 ni -8 ga qo'shish.

$$x=\frac{-1±\sqrt{-7}}{2}$$

-7 ning kvadrat ildizini chiqarish.

$$x=\frac{-1±\sqrt{7}i}{2}$$

x=\frac{-1±\sqrt{7}i}{2} tenglamasini yeching, bunda ± musbat. -1 ni i\sqrt{7} ga qo'shish.

$$x=\frac{-1+\sqrt{7}i}{2}$$

x=\frac{-1±\sqrt{7}i}{2} tenglamasini yeching, bunda ± manfiy. -1 dan i\sqrt{7} ni ayirish.

$$x=\frac{-\sqrt{7}i-1}{2}$$

Tenglama yechildi.

$$x=\frac{-1+\sqrt{7}i}{2} x=\frac{-\sqrt{7}i-1}{2}$$

Kvadratni yakunlash bo'yicha qadamlar

Bu kabi kvadrat tenglamalarni kvadratni yakunlab yechish mumkin. Kvadratni yechish uchun tenglama avval ushbu shaklda bo'lishi shart: x^{2}+bx=c.

$$x^{2}+x+2=0$$

Tenglamaning ikkala tarafidan 2 ni ayirish.

$$x^{2}+x+2-2=-2$$

O‘zidan 2 ayirilsa 0 qoladi.

$$x^{2}+x=-2$$

1 ni bo‘lish, x shartining koeffitsienti, 2 ga \frac{1}{2} olish uchun. Keyin, \frac{1}{2} ning kvadratini tenglamaning ikkala tarafiga qo‘shing. Ushbu qadam tenglamaning chap qismini mukammal kvadrat sifatida hosil qiladi.

$$x^{2}+x+\left(\frac{1}{2}\right)^{2}=-2+\left(\frac{1}{2}\right)^{2}$$

Kasrning ham suratini, ham maxrajini kvadratga ko'paytirib \frac{1}{2} kvadratini chiqarish.

$$x^{2}+x+\frac{1}{4}=-2+\frac{1}{4}$$

-2 ni \frac{1}{4} ga qo'shish.

$$x^{2}+x+\frac{1}{4}=-\frac{7}{4}$$

x^{2}+x+\frac{1}{4} omili. Odatda, x^{2}+bx+c mukammal kvadrat bo'lsa, u doimo \left(x+\frac{b}{2}\right)^{2} omil sifatida bo'lishi mumkin.

$$\left(x+\frac{1}{2}\right)^{2}=-\frac{7}{4}$$

Tenglamaning ikkala tarafining kvadrat ildizini chiqarish.

$$\sqrt{\left(x+\frac{1}{2}\right)^{2}}=\sqrt{-\frac{7}{4}}$$

Qisqartirish.

$$x+\frac{1}{2}=\frac{\sqrt{7}i}{2} x+\frac{1}{2}=-\frac{\sqrt{7}i}{2}$$

Tenglamaning ikkala tarafidan \frac{1}{2} ni ayirish.

$$x=\frac{-1+\sqrt{7}i}{2} x=\frac{-\sqrt{7}i-1}{2}$$