If inequality kx^2 -2x + k ≥ 0 holds good for atleast one real 'x' , then complete s

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4-2.Quadratic Equations and Inequations

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If the inequality $kx^2 -2x + k \geq 0$ holds good for atleast one real $'x'$ , then the complete set of values of $'k'$ is

A

$[-1,1]$

B

$\left( { - \infty ,1} \right]$

C

$\phi $

D

$\left( { - 1,\infty } \right]$

Solution

${\rm{k}} \ge \frac{{2{\rm{x}}}}{{\underbrace {{{\rm{x}}^2} + 1}_{\left[ { – 1,1} \right]}}}$

$\Rightarrow \mathrm{k} \geq-1$

Standard 11

Mathematics

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