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Statement-1: If a, b, c in Q and 2^(1//3...

Statement-1: `If a, b, c in Q and 2^(1//3)` is a root of `ax^(2) + bx + c = 0`, then a = b = c = 0.
Statement-2: A polynomial equation with rational coefficients cannot have irrational roots.

A

Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1.

B

Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for Statement-1.

C

Statement-1 is True, Statement-2 is False.

D

Statement-1 is False, Statement-2 is True.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze both statements provided in the question. **Step 1: Analyze Statement 1** Statement 1 claims that if \( a, b, c \in \mathbb{Q} \) and \( 2^{1/3} \) is a root of the quadratic equation \( ax^2 + bx + c = 0 \), then \( a = b = c = 0 \). 1. **Assumption**: Let \( a, b, c \) be rational numbers (i.e., \( a, b, c \in \mathbb{Q} \)). 2. **Substituting the root**: Since \( 2^{1/3} \) is a root, substituting \( x = 2^{1/3} \) into the equation gives: \[ a(2^{1/3})^2 + b(2^{1/3}) + c = 0 \] Simplifying this, we have: \[ a(2^{2/3}) + b(2^{1/3}) + c = 0 \] 3. **Multiplying by the LCM**: To eliminate the irrational terms, we can multiply the entire equation by \( 2^{3/3} \) (which is 2) to obtain: \[ 2a(2^{2/3}) + 2b(2^{1/3}) + 2c = 0 \] This simplifies to: \[ 2a(2^{2/3}) + 2b(2^{1/3}) + 2c = 0 \] 4. **Analyzing the coefficients**: Since \( a, b, c \) are rational, the left-hand side must also be rational. However, \( 2^{1/3} \) and \( 2^{2/3} \) are irrational, leading to a contradiction unless \( a = b = c = 0 \). 5. **Conclusion for Statement 1**: The only solution that avoids contradiction is \( a = b = c = 0 \). Thus, Statement 1 is **true**. **Step 2: Analyze Statement 2** Statement 2 states that a polynomial equation with rational coefficients cannot have irrational roots. 1. **Counterexample**: Consider the polynomial \( x^3 - 2 = 0 \). This polynomial has rational coefficients (1 and -2). 2. **Finding the roots**: The root of this polynomial is \( x = 2^{1/3} \), which is irrational. 3. **Conclusion for Statement 2**: Since we found a polynomial with rational coefficients that has an irrational root, Statement 2 is **false**. **Final Conclusion**: - Statement 1 is **true**. - Statement 2 is **false**. ---

To solve the problem, we need to analyze both statements provided in the question. **Step 1: Analyze Statement 1** Statement 1 claims that if \( a, b, c \in \mathbb{Q} \) and \( 2^{1/3} \) is a root of the quadratic equation \( ax^2 + bx + c = 0 \), then \( a = b = c = 0 \). 1. **Assumption**: Let \( a, b, c \) be rational numbers (i.e., \( a, b, c \in \mathbb{Q} \)). 2. **Substituting the root**: Since \( 2^{1/3} \) is a root, substituting \( x = 2^{1/3} \) into the equation gives: \[ ...
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  2. Statement-1: If alpha and beta are real roots of the quadratic equatio...

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  4. Statement I: x^2-5x+6<0 if 2 < x < 3 Statement II: If alpha and beta, ...

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  5. about to only mathematics

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  7. Statement-1: If x^(2) + ax + 4 gt 0 "for all" x in R, then a in (-4, 4...

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  8. If the roots of the equation ax^2 + bx + c = 0, a != 0 (a, b, c are re...

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  9. Statement (1) : If a and b are integers and roots of x^2 + ax + b = 0 ...

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  10. Statement-1: If a, b, c are distinct real numbers, then a((x-b)(x-c))/...

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  11. Let f(x)=a x^2+bx +c a ,b ,c in R. If f(x) takes real values for re...

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  12. Statement-1: If a, b, c in R and 2a + 3b + 6c = 0, then the equation a...

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  13. Statement-1: If a ne 0 and the equation ax^(2) + bx + c = 0 has two ro...

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  14. Statement-1: If a, b, c in Q and 2^(1//3) is a root of ax^(2) + bx + c...

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  15. Statement-1: If f(x) = 1 + x + (x^(2))/(2!) + (x^(3))/(3!) + (x^(4))/(...

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  16. Given that for all real x, the expression (x^(2)-2x+4)/(x^(2)+2x+4) l...

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  17. Let a, b, c be real numbers such that ax^(2) + bx + c = 0 and x^(2) + ...

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  20. Consider a quadratic equation ax^(2) + bx + c = 0, where 2a + 3b + 6c ...

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