The value(s) of $k$ for which the quadratic equation $2 x^{2}+k x+2=0$ has equal roots, is\

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Professor PC Thomas Classes · Answer

(b) :Given quadratic equation is $$ 2 x^{2}+k x+2=0 $$ Since, the equation has equal roots. $$ \begin{aligned} & 	herefore 	ext { Discriminant }=0 \ & \Rightarrow k^{2}-4 	imes 2 	imes 2=0 \Rightarrow k^{2}-16=0 \ & \Rightarrow k^{2}=16 \Rightarrow k= \pm 4 \end{aligned} $$