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Statement-1: If x^(2) + ax + 4 gt 0 "for...

Statement-1: `If x^(2) + ax + 4 gt 0 "for all" x in R`, then `a in (-4, 4)`.
Statement-2: The sign of quadratic expression `ax^(2) + bx + c` is always same as that of 'a' except for those values of x which lie between its 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.

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The correct Answer is:
To solve the problem, we need to analyze both statements provided and determine their validity step by step. ### Step 1: Analyze Statement 1 **Statement 1:** If \( x^2 + ax + 4 > 0 \) for all \( x \in \mathbb{R} \), then \( a \in (-4, 4) \). 1. **Condition for a Quadratic to be Positive:** For the quadratic expression \( x^2 + ax + 4 \) to be greater than zero for all real numbers \( x \), two conditions must be satisfied: - The coefficient of \( x^2 \) (which is 1) must be greater than zero. - The discriminant of the quadratic must be less than zero. 2. **Calculate the Discriminant:** The discriminant \( D \) of the quadratic \( x^2 + ax + 4 \) is given by: \[ D = b^2 - 4ac = a^2 - 4 \cdot 1 \cdot 4 = a^2 - 16 \] 3. **Set the Discriminant Condition:** For the quadratic to be positive for all \( x \), we need: \[ D < 0 \implies a^2 - 16 < 0 \implies a^2 < 16 \] 4. **Solve the Inequality:** Taking the square root of both sides gives: \[ -4 < a < 4 \] Thus, \( a \in (-4, 4) \). ### Conclusion for Statement 1: Statement 1 is **True**. --- ### Step 2: Analyze Statement 2 **Statement 2:** The sign of the quadratic expression \( ax^2 + bx + c \) is always the same as that of \( a \) except for those values of \( x \) which lie between its roots. 1. **Understanding Quadratic Behavior:** - If \( a > 0 \), the parabola opens upwards. The quadratic will be positive outside the roots and negative between the roots. - If \( a < 0 \), the parabola opens downwards. The quadratic will be negative outside the roots and positive between the roots. 2. **Conclusion for Statement 2:** The statement correctly describes the behavior of quadratic functions. Thus, Statement 2 is also **True**. ### Final Conclusion: - **Statement 1 is True.** - **Statement 2 is True.** - However, Statement 2 does not serve as a correct explanation for Statement 1. ### Answer: The correct option is: **Second option: Statement 1 is true, Statement 2 is true, and Statement 2 is not a correct explanation for Statement 1.** ---

To solve the problem, we need to analyze both statements provided and determine their validity step by step. ### Step 1: Analyze Statement 1 **Statement 1:** If \( x^2 + ax + 4 > 0 \) for all \( x \in \mathbb{R} \), then \( a \in (-4, 4) \). 1. **Condition for a Quadratic to be Positive:** For the quadratic expression \( x^2 + ax + 4 \) to be greater than zero for all real numbers \( x \), two conditions must be satisfied: - The coefficient of \( x^2 \) (which is 1) must be greater than zero. ...
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OBJECTIVE RD SHARMA ENGLISH-QUADRATIC EXPRESSIONS AND EQUATIONS -Section II - Assertion Reason Type
  1. If alpha and beta are the roots of the equation x^(2)-ax+b=0and A(n)=a...

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  2. Statement-1: If alpha and beta are real roots of the quadratic equatio...

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  3. Statement-1: If a, b, c, A, B, C are real numbers such that a lt b lt ...

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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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  6. Statement-1: There is a value of k for which the equation x^(3) - 3x +...

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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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  18. Statement-1: The cubic equation 4x^(3) - 15x^(2)+14x-5 = 0 has a root ...

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  19. Statement-1: The equation (pi^(e))/(x-e)+(e^(pi))/(x-pi)+(pi^(pi)+e^(e...

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

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