x^2+2x-1=0 eching

$${ x }^{ 2 } +2x-1=0$$

x uchun yechish (complex solution)

$$x=\sqrt{2}-1\approx 0,414213562$$

$$x=-\left(\sqrt{2}+1\right)\approx -2,414213562$$

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.

$$x^{2}+2x-1=0$$

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

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

2 kvadratini chiqarish.

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

-4 ni -1 marotabaga ko'paytirish.

$$x=\frac{-2±\sqrt{4+4}}{2}$$

4 ni 4 ga qo'shish.

$$x=\frac{-2±\sqrt{8}}{2}$$

8 ning kvadrat ildizini chiqarish.

$$x=\frac{-2±2\sqrt{2}}{2}$$

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

$$x=\frac{2\sqrt{2}-2}{2}$$

-2+2\sqrt{2} ni 2 ga bo'lish.

$$x=\sqrt{2}-1$$

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

$$x=\frac{-2\sqrt{2}-2}{2}$$

-2-2\sqrt{2} ni 2 ga bo'lish.

$$x=-\sqrt{2}-1$$

Tenglama yechildi.

$$x=\sqrt{2}-1 x=-\sqrt{2}-1$$

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.

$$x^{2}+2x-1=0$$

1 ni tenglamaning ikkala tarafiga qo'shish.

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

O‘zidan -1 ayirilsa 0 qoladi.

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

0 dan -1 ni ayirish.

$$x^{2}+2x=1$$

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

$$x^{2}+2x+1^{2}=1+1^{2}$$

1 kvadratini chiqarish.

$$x^{2}+2x+1=1+1$$

1 ni 1 ga qo'shish.

$$x^{2}+2x+1=2$$

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

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

Tenglamaning ikkala tarafining kvadrat ildizini chiqarish.

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

Qisqartirish.

$$x+1=\sqrt{2} x+1=-\sqrt{2}$$

Tenglamaning ikkala tarafidan 1 ni ayirish.

$$x=\sqrt{2}-1 x=-\sqrt{2}-1$$

x uchun yechish

$$x=\sqrt{2}-1\approx 0,414213562$$

$$x=-\sqrt{2}-1\approx -2,414213562$$

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.

$$x^{2}+2x-1=0$$

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

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

2 kvadratini chiqarish.

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

-4 ni -1 marotabaga ko'paytirish.

$$x=\frac{-2±\sqrt{4+4}}{2}$$

4 ni 4 ga qo'shish.

$$x=\frac{-2±\sqrt{8}}{2}$$

8 ning kvadrat ildizini chiqarish.

$$x=\frac{-2±2\sqrt{2}}{2}$$

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

$$x=\frac{2\sqrt{2}-2}{2}$$

-2+2\sqrt{2} ni 2 ga bo'lish.

$$x=\sqrt{2}-1$$

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

$$x=\frac{-2\sqrt{2}-2}{2}$$

-2-2\sqrt{2} ni 2 ga bo'lish.

$$x=-\sqrt{2}-1$$

Tenglama yechildi.

$$x=\sqrt{2}-1 x=-\sqrt{2}-1$$

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.

$$x^{2}+2x-1=0$$

1 ni tenglamaning ikkala tarafiga qo'shish.

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

O‘zidan -1 ayirilsa 0 qoladi.

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

0 dan -1 ni ayirish.

$$x^{2}+2x=1$$

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

$$x^{2}+2x+1^{2}=1+1^{2}$$

1 kvadratini chiqarish.

$$x^{2}+2x+1=1+1$$

1 ni 1 ga qo'shish.

$$x^{2}+2x+1=2$$

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

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

Tenglamaning ikkala tarafining kvadrat ildizini chiqarish.

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

Qisqartirish.

$$x+1=\sqrt{2} x+1=-\sqrt{2}$$

Tenglamaning ikkala tarafidan 1 ni ayirish.

$$x=\sqrt{2}-1 x=-\sqrt{2}-1$$