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If the smaller root of the equation `x^2−ax+4=0` lies between `−1` and `−2`, then belongs to

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The correct Answer is:
3

`(beta - alpha) = ((beta + h)-(alpha + h))`
`(beta + alpha)^(2) -4alphabeta = [(beta + h) +(alpha + h)]^(2) - 4(beta + h) (alpha + h)`
`(-b_(1))^(2) - 4c_(1) = (-b_(2))^(2) - 4c_(2)`
`D_(1) = D_(2)`
The least value of f(x) is .
`-(D_(1))/(4) = - (1)/(4) and D_(2) = 1`
Therefore, the least value of
`g(x)` is `-(D_(2))/(4) = -(1)/(4)`
The least value of the of g(x) occurs at
`-(b_(2))/(2)=(7)/(2)` or `b_(2) = -7`
Now, `b_(2)^(2)-4c_(2) = D_(2)`
or ` 49-4c_(2) = 1` or `(48)/(4) = c_(2) or c_(2) = 12`
`rArr x^(2) - 7x + 12 = 0` or `x = 3,4`
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CENGAGE-THEORY OF EQUATIONS-Exercise (Comprehension)
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  3. If the smaller root of the equation x^2−ax+4=0 lies between −1 and −2,...

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  4. In the given figure, vertices of Delta ABC lie on y = f(x) = ax^2 + bx...

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  5. In the given figure, vertices of Delta ABC lie on y = f(x) = ax^2 + bx...

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  6. In the given figure, vertices of Delta ABC lie on y = f(x) = ax^2 + bx...

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  7. Let f(x) =4x^2-4ax+a^2-2a+2 be a quadratic polynomial in x,a be any re...

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  8. Let f(x) =4x^2-4ax+a^2-2a+2 be a quadratic polynomial in x,a be any re...

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  9. Let f(x) =4x^2-4ax+a^2-2a+2 be a quadratic polynomial in x,a be any re...

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  10. Consider the equaiton 2 + |x^(2) + 4x + 3|= m , m in R Set of all ...

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  11. Consider the equaiton 2 + |x^(2) + 4x + 3| = m , m in R Set of all...

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  12. Consider the equaiton 2 + |x^(2) + 4x + 3|= m , m in R Set of all v...

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