Home
Class 11
MATHS
Statement-1: If a, b, c in R and 2a + 3b...

Statement-1: `If a, b, c in R and 2a + 3b + 6c = 0`, then the equation `ax^(2) + bx + c = 0` has at least one real root in (0, 1).
Statement-2: If f(x) is a polynomial which assumes both positive and negative values, then it has at least one real root.

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 given in the question. ### Step 1: Analyze Statement-2 Statement-2 states that if \( f(x) \) is a polynomial that assumes both positive and negative values, then it has at least one real root. **Solution:** This statement is true because of the Intermediate Value Theorem. If a continuous function (like a polynomial) takes on both positive and negative values, it must cross the x-axis at least once. Therefore, there exists at least one real root. ### Step 2: Analyze Statement-1 Statement-1 states that if \( 2a + 3b + 6c = 0 \), then the quadratic equation \( ax^2 + bx + c = 0 \) has at least one real root in the interval \( (0, 1) \). **Solution:** 1. **Define the function:** Let \( f(x) = ax^2 + bx + c \). 2. **Evaluate \( f(0) \):** \[ f(0) = c \] 3. **Evaluate \( f(1) \):** \[ f(1) = a(1)^2 + b(1) + c = a + b + c \] 4. **Use the given condition:** We know that \( 2a + 3b + 6c = 0 \). We can manipulate this equation to express \( c \): \[ c = -\frac{2a + 3b}{6} \] 5. **Substituting \( c \) into \( f(0) \) and \( f(1) \):** - From the above, we have \( f(0) = c = -\frac{2a + 3b}{6} \). - For \( f(1) \): \[ f(1) = a + b + c = a + b - \frac{2a + 3b}{6} \] - Combine the terms: \[ f(1) = a + b - \frac{2a + 3b}{6} = \frac{6a + 6b - 2a - 3b}{6} = \frac{4a + 3b}{6} \] 6. **Check the signs of \( f(0) \) and \( f(1) \):** - If \( f(0) = c \) and \( f(1) = \frac{4a + 3b}{6} \), we need to analyze the signs of these two expressions. - Since \( 2a + 3b + 6c = 0 \), we can see that if \( c \) is negative (which could happen if \( 2a + 3b > 0 \)), then \( f(0) < 0 \). - If \( 4a + 3b < 0 \), then \( f(1) < 0 \). - If \( 4a + 3b > 0 \), then \( f(1) > 0 \). 7. **Conclusion using Rolle's Theorem:** Since \( f(0) \) and \( f(1) \) can take opposite signs, by the Intermediate Value Theorem (or Rolle's Theorem), there must be at least one root in the interval \( (0, 1) \). ### Final Conclusion: Both statements are true. Statement-1 is true because the quadratic equation has at least one real root in the interval \( (0, 1) \) given the condition \( 2a + 3b + 6c = 0 \). Statement-2 is also true as it follows from the Intermediate Value Theorem.

To solve the problem, we need to analyze both statements given in the question. ### Step 1: Analyze Statement-2 Statement-2 states that if \( f(x) \) is a polynomial that assumes both positive and negative values, then it has at least one real root. **Solution:** This statement is true because of the Intermediate Value Theorem. If a continuous function (like a polynomial) takes on both positive and negative values, it must cross the x-axis at least once. Therefore, there exists at least one real root. ...
Promotional Banner

Topper's Solved these Questions

  • QUADRATIC EXPRESSIONS AND EQUATIONS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Exercise|138 Videos
  • QUADRATIC EXPRESSIONS AND EQUATIONS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Chapter Test|50 Videos
  • QUADRATIC EXPRESSIONS AND EQUATIONS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Section I - Solved Mcqs|123 Videos
  • PROBABILITY

    OBJECTIVE RD SHARMA ENGLISH|Exercise Chapter Test|45 Videos
  • SEQUENCES AND SERIES

    OBJECTIVE RD SHARMA ENGLISH|Exercise Chapter Test|59 Videos

Similar Questions

Explore conceptually related problems

If 2a+3b+6c = 0, then show that the equation a x^2 + bx + c = 0 has atleast one real root between 0 to 1.

If 2a+3b+6c = 0, then show that the equation a x^2 + bx + c = 0 has atleast one real root between 0 to 1.

If 4a+2b+c=0 , then the equation 3ax^(2)+2bx+c=0 has at least one real lying in the interval

If a, b and c are positive real and a = 2b + 3c , then the equation ax^(2) + bx + c = 0 has real roots for

If a, b, c are positive and a = 2b + 3c, then roots of the equation ax^(2) + bx + c = 0 are real for

If the equation ax^(2) + bx + c = 0, a,b, c, in R have non -real roots, then

If a, b, c in R and the quadratic equation x^2 + (a + b) x + c = 0 has no real roots then

If a, b, c ∈ R, a ≠ 0 and the quadratic equation ax^2 + bx + c = 0 has no real root, then show that (a + b + c) c > 0

The quadratic equation ax^(2)+bx+c=0 has real roots if:

Statement 1: If 27 a+9b+3c+d=0, then the equation f(x)=4a x^3+3b x^2+2c x+d=0 has at least one real root lying between (0,3)dot Statement 2: If f(x) is continuous in [a,b], derivable in (a , b) such that f(a)=f(b), then there exists at least one point c in (a , b) such that f^(prime)(c)=0.

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...

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

  5. about to only mathematics

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |

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

    Text Solution

    |