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How many real roots of the equations x^(...

How many real roots of the equations `x^(2) + 3|x| +2 = 0` have ?

A

zero

B

one

C

two

D

Four

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AI Generated Solution

The correct Answer is:
To solve the equation \( x^2 + 3|x| + 2 = 0 \) and determine how many real roots it has, we will consider two cases based on the definition of the absolute value function. ### Step 1: Identify Cases Based on Absolute Value The absolute value function \( |x| \) can be expressed as: - \( |x| = x \) when \( x \geq 0 \) - \( |x| = -x \) when \( x < 0 \) ### Step 2: Case 1: \( x \geq 0 \) In this case, we substitute \( |x| \) with \( x \): \[ x^2 + 3x + 2 = 0 \] Now, we will factor the quadratic equation: \[ (x + 1)(x + 2) = 0 \] Setting each factor to zero gives: \[ x + 1 = 0 \quad \Rightarrow \quad x = -1 \] \[ x + 2 = 0 \quad \Rightarrow \quad x = -2 \] However, since we are in the case where \( x \geq 0 \), neither \( x = -1 \) nor \( x = -2 \) are valid solutions. Therefore, there are **no real roots** in this case. ### Step 3: Case 2: \( x < 0 \) In this case, we substitute \( |x| \) with \( -x \): \[ x^2 - 3x + 2 = 0 \] Now, we will factor this quadratic equation: \[ (x - 1)(x - 2) = 0 \] Setting each factor to zero gives: \[ x - 1 = 0 \quad \Rightarrow \quad x = 1 \] \[ x - 2 = 0 \quad \Rightarrow \quad x = 2 \] However, since we are in the case where \( x < 0 \), neither \( x = 1 \) nor \( x = 2 \) are valid solutions. Therefore, there are **no real roots** in this case as well. ### Conclusion Since both cases yield no valid solutions, we conclude that the equation \( x^2 + 3|x| + 2 = 0 \) has **zero real roots**. ### Final Answer The number of real roots of the equation is **0**. ---
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