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Can someone please help me with the problem? Please show your work.

Directions: Solve the following. Which is a solution to 3x^2 + 2 =0?

(√6/3)i

2/3

1

(2/3)i​​​​

User Joe Pym
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1 Answer

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Final answer:

The quadratic equation 3x^2 + 2 = 0 has two complex solutions, x = ±(sqrt(2/3))i. Neither of the student's proposed solutions is correct. The correct solutions involve the square root of 2/3 multiplied by the imaginary unit i.

Step-by-step explanation:

The student's question pertains to finding the solutions to the quadratic equation 3x2 + 2 = 0. To solve this equation, we must use the square root method since the equation is already set with the x2 term isolated and doesn't have an x term (meaning b = 0 in the general form of ax2 + bx + c = 0).

First, we isolate x2 as follows:

  1. Subtract 2 from both sides of the equation: 3x2 = -2.
  2. Divide both sides of the equation by 3 to get x2 = -2/3.
  3. Take the square root of both sides. Since we are dealing with a negative number, we introduce i, the imaginary unit, such that i2 = -1, to get x = ±sqrt(-2/3).
  4. Simplify the square root to get x = ±(sqrt(2/3))i.

We obtained two complex solutions: x = (sqrt(2/3))i and x = -(sqrt(2/3))i, since the square root of a negative number results in an imaginary number. Thus, neither of the student's proposed solutions ((√6/3)i, 2/3, or (2/3)i) is correct. Instead, we discovered that the correct solutions involve the square root of 2/3 multiplied by i.

User Flopga Slays
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