Math Problem Statement

Determine which of these potential solutions make the equation x^2 + 2x + 3 = 0 true. Option 1: x = -1 ± i√2, Option 2: x = -1 ± 2i, Option 3: x = 1 ± i√2.

Solution

Let's solve the quadratic equation x2+2x+3=0x^2 + 2x + 3 = 0 and determine the correct solution.

Step 1: Use the Quadratic Formula

The quadratic formula is:

x=b±b24ac2ax = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}

For the equation x2+2x+3=0x^2 + 2x + 3 = 0:

  • a=1a = 1
  • b=2b = 2
  • c=3c = 3

Step 2: Calculate the Discriminant

b24ac=(2)24(1)(3)=412=8b^2 - 4ac = (2)^2 - 4(1)(3) = 4 - 12 = -8

Since the discriminant is negative, the solutions involve imaginary numbers.

Step 3: Compute the Square Root

8=8i=22i\sqrt{-8} = \sqrt{8} i = 2\sqrt{2} i

Step 4: Compute the Two Solutions

x=2±22i2x = \frac{-2 \pm 2\sqrt{2} i}{2}

x=1±i2x = -1 \pm i\sqrt{2}

Step 5: Identify the Correct Option

Comparing with the given options:

  • Option 1: x=1±i2x = -1 \pm i\sqrt{2} ✅ (Correct)
  • Option 2: x=1±2ix = -1 \pm 2i ❌ (Incorrect)
  • Option 3: x=1±i2x = 1 \pm i\sqrt{2} ❌ (Incorrect)

Final Answer:

The correct choice is Option 1.


Would you like a detailed explanation of any step?

Here are five related questions to explore further:

  1. How do we determine the nature of the roots using the discriminant?
  2. What are the implications of a negative discriminant in a quadratic equation?
  3. How can we verify solutions by substituting them back into the equation?
  4. What is the geometric interpretation of complex roots in quadratic equations?
  5. How does the quadratic formula derive from completing the square?

Tip: Always check the discriminant before solving a quadratic equation to determine whether the roots are real or complex.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Quadratic Equations
Complex Numbers

Formulas

Quadratic Formula: x = (-b ± √(b² - 4ac)) / 2a

Theorems

Quadratic Formula
Discriminant Analysis

Suitable Grade Level

Grades 8-10