Answered

What are the solutions for the equation [tex]$2x^2 + 36 = 0$[/tex]?

A. [tex]$x = \pm 6$[/tex]

B. [tex][tex]$x = \pm 6i$[/tex][/tex]

C. [tex]$x = \pm 3 \sqrt{2}$[/tex]

D. [tex]$x = \pm 3i \sqrt{2}$[/tex]



Answer :

To solve the equation [tex]\( 2x^2 + 36 = 0 \)[/tex], we will proceed with a detailed, step-by-step approach:

1. Start with the given equation:
[tex]\[ 2x^2 + 36 = 0 \][/tex]

2. Isolate the [tex]\( x^2 \)[/tex] term by subtracting 36 from both sides:
[tex]\[ 2x^2 = -36 \][/tex]

3. Divide both sides of the equation by 2 to solve for [tex]\( x^2 \)[/tex]:
[tex]\[ x^2 = -18 \][/tex]

4. Recognize that the right side is negative, indicating complex solutions. Now, take the square root of both sides:
[tex]\[ x = \pm \sqrt{-18} \][/tex]

5. Rewrite the square root of a negative number using the imaginary unit [tex]\( i \)[/tex] ([tex]\( \sqrt{-1} = i \)[/tex]):
[tex]\[ x = \pm \sqrt{18} \cdot i \][/tex]

6. Simplify [tex]\( \sqrt{18} \)[/tex]. Note that 18 can be factored as [tex]\( 9 \times 2 \)[/tex]:
[tex]\[ \sqrt{18} = \sqrt{9 \times 2} = \sqrt{9} \cdot \sqrt{2} = 3\sqrt{2} \][/tex]

7. Combine this result with the factor [tex]\( i \)[/tex]:
[tex]\[ x = \pm 3\sqrt{2} \cdot i \][/tex]

So, the solutions to the equation [tex]\( 2x^2 + 36 = 0 \)[/tex] are [tex]\( x = \pm 3i\sqrt{2} \)[/tex].

Therefore, the correct option is:
D. [tex]\( x = \pm 3i\sqrt{2} \)[/tex]