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Assertion (A), The equation x^(2)+ 2|x|+...

Assertion (A), The equation `x^(2)+ 2|x|+3=0` has no real root.
Reason (R): In a quadratic equation `ax^(2)+bx+c=0, a,b,c in R` discriminant is less than zero then the equation has no real root.

A

Both A, R are true and R explain A

B

Both A, R are true but R does't explain A

C

A is true R is false

D

A is false R is true

Text Solution

AI Generated Solution

The correct Answer is:
To solve the assertion and reason question regarding the quadratic equation \( x^2 + 2|x| + 3 = 0 \), we will analyze the assertion and reason step by step. ### Step 1: Understand the Assertion The assertion states that the equation \( x^2 + 2|x| + 3 = 0 \) has no real roots. ### Step 2: Analyze the Equation The equation involves an absolute value, which means we need to consider two cases based on the definition of the absolute value. 1. **Case 1:** When \( x \geq 0 \), \( |x| = x \). - The equation becomes: \[ x^2 + 2x + 3 = 0 \] 2. **Case 2:** When \( x < 0 \), \( |x| = -x \). - The equation becomes: \[ x^2 - 2x + 3 = 0 \] ### Step 3: Calculate the Discriminant for Each Case To determine if there are real roots, we will calculate the discriminant \( D \) for both cases. 1. **For Case 1:** \( x^2 + 2x + 3 = 0 \) - Here, \( a = 1, b = 2, c = 3 \). - The discriminant \( D \) is given by: \[ D = b^2 - 4ac = 2^2 - 4 \cdot 1 \cdot 3 = 4 - 12 = -8 \] - Since \( D < 0 \), there are no real roots for this case. 2. **For Case 2:** \( x^2 - 2x + 3 = 0 \) - Here, \( a = 1, b = -2, c = 3 \). - The discriminant \( D \) is given by: \[ D = (-2)^2 - 4 \cdot 1 \cdot 3 = 4 - 12 = -8 \] - Again, since \( D < 0 \), there are no real roots for this case as well. ### Step 4: Conclusion on the Assertion Since both cases yield a negative discriminant, we conclude that the assertion is true: the equation \( x^2 + 2|x| + 3 = 0 \) has no real roots. ### Step 5: Analyze the Reason The reason states that in a quadratic equation \( ax^2 + bx + c = 0 \), if the discriminant is less than zero, then the equation has no real roots. This is a true statement and correctly explains why the assertion holds. ### Final Conclusion Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the correct option is: **Option A:** Assertion and Reason both are true, and Reason explains Assertion. ---
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