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If the roots of x^(2)-bx+c=0 be two cons...

If the roots of `x^(2)-bx+c=0` be two consecutive integers, then find the value of `b^(2)-4c`.

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To solve the problem, we need to find the value of \( b^2 - 4c \) given that the roots of the quadratic equation \( x^2 - bx + c = 0 \) are two consecutive integers. ### Step-by-Step Solution: 1. **Identify the Roots**: Let the roots of the equation be \( \alpha \) and \( \beta \). Since they are consecutive integers, we can express them as \( \alpha = n \) and \( \beta = n + 1 \) for some integer \( n \). 2. **Use Vieta's Formulas**: According to Vieta's formulas, for the quadratic equation \( x^2 - bx + c = 0 \): - The sum of the roots \( \alpha + \beta = b \) - The product of the roots \( \alpha \cdot \beta = c \) Therefore, we can write: \[ n + (n + 1) = b \implies 2n + 1 = b \] \[ n(n + 1) = c \implies c = n^2 + n \] 3. **Substitute \( b \) and \( c \)**: Now we have expressions for \( b \) and \( c \): - \( b = 2n + 1 \) - \( c = n^2 + n \) 4. **Calculate \( b^2 - 4c \)**: We need to find \( b^2 - 4c \): \[ b^2 = (2n + 1)^2 = 4n^2 + 4n + 1 \] \[ 4c = 4(n^2 + n) = 4n^2 + 4n \] Now substituting these into the expression: \[ b^2 - 4c = (4n^2 + 4n + 1) - (4n^2 + 4n) \] Simplifying this gives: \[ b^2 - 4c = 1 \] 5. **Final Result**: Thus, the value of \( b^2 - 4c \) is \( 1 \).
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ICSE-QUADRATIC EQUATIONS-EXERCISE 10 (c)
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  3. Find the value of a for which one root of the quadratic equation (a^(2...

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  6. If alpha and beta are the roots of the equation 2x^(2)+3x+2=0, find th...

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  7. Find the equation whose roots are (alpha)/(beta) and (beta)/(alpha), w...

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  8. If alpha and beta are the roots of the equation 2x^(2)-3x+1=0, form th...

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  9. If a ne b and a^(2)=5a-3,b^(2)=5b-3, then form that equation whose roo...

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  10. Given that alpha and beta are the roots of the equation x^(2)=x+7. (...

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  11. Given that alpha and beta are the roots of the equation x^(2)-x+7=0, f...

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  12. Given that alpha and beta are the roots of the equation 2x^(2)-3x+4=0,...

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  13. The roots of the quadratic equation x^(2)+px+8=0 are alpha and beta. ...

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  14. If the roots of x^(2)-bx+c=0 be two consecutive integers, then find th...

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  15. The roots of the equation px^(2)-2(p+1)x+3p=0 are alpha and beta. If a...

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  16. The roots of the equation ax^(2)+bx+c=0 are alpha and beta. Form the q...

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  17. Two candidates attempt to solve a quadratic equation of the form x^(2)...

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  18. Given that alpha and beta are the roots of the equation x^(2)=7x+4, ...

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  19. The ratio of the roots of the equation x^(2)+alphax+alpha+2=0 is 2. fi...

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  20. If (1-p) is a root of the quadratic equation x^(2)+px+(1-p)=0, then it...

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