Consider the quadratic equation (c - 5)x^2 - | vedclass

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(D) Let $f(x) = (c - 5)x^2 - 2cx + (c - 4)$.For one root to lie in $(0, 2)$ and the other in $(2, 3)$,the value of $f(x)$ must change sign at $x=2$.Ca

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$11$

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(D) Let $f(x) = (c - 5)x^2 - 2cx + (c - 4)$.For one root to lie in $(0, 2)$ and the other in $(2, 3)$,the value of $f(x)$ must change sign at $x=2$.Case $I$: If $c - 5 > 0$ (i.e.,$c > 5$),then $f(2) $f(2) = (c - 5)(2)^2 - 2c(2) + (c - 4) = 4c - 20 - 4c + c - 4 = c - 24$.So,$c - 24 Also,$f(0) > 0$ $\Rightarrow c - 4 > 0$ $\Rightarrow c > 4$.And $f(3) > 0$ $\Rightarrow (c - 5)(9) - 2c(3) + (c - 4) > 0$ $\Rightarrow 9c - 45 - 6c + c - 4 > 0$ $\Rightarrow 4c - 49 > 0$ $\Rightarrow c > 12.25$.Combining these,$12.25 Case $II$: If $c - 5  0$.$c - 24 > 0 \Rightarrow c > 24$,which contradicts $c Thus,there are $11$ such integral values.

Quadratic expression	The minimum value
i) $x^2 + 4x + 6$	a) $1$
ii) $x^2 - 2x + 5$	b) $2$
iii) $x^2 + 6x + 18$	c) $4$
iv) $x^2 - 4x + 5$	d) $9$

Consider the quadratic equation $(c - 5)x^2 - 2cx + (c - 4) = 0$,where $c \ne 5$. Let $S$ be the set of all integral values of $c$ for which one root of the equation lies in the interval $(0, 2)$ and the other root lies in the interval $(2, 3)$. Then the number of elements in $S$ is

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