Question

Find the value of k for which the quadratic equation 2 x square + kx + 2 is equal to zero has equal roots

Answer 1

Answer:

this is right answer

hope this helps you

Answer 2

$\blue{\bold{\underline{\underline{Answer:}}}}$

$\green{\tt{\therefore{Value\:of\:k=\pm 4}}}$

$\orange{\bold{\underline{\underline{Step-by-step\:explanation:}}}}$

$\green{ \underline \bold{Given : }} \\ \tt{ : \implies 2x^{2} +kx + 2 = 0 }\\ \\ \red{ \underline \bold{To \: Find : }} \\ \tt{: \implies value \: of \: k = ?}$

• According to given question :

$\tt{ : \implies 2x^{2} +kx + 2= 0} \\ \\ \tt{\circ \: a = 2} \\ \\ \tt{\circ \: b = k}\\\\ \tt{\circ \:c = 2}\\ \\ \bold{Discriminant \: = 0} \\ \\ \tt{: \rightarrow \: D \implies {b}^{2} - 4ac = 0 } \\ \\ \tt{: \implies {b}^{2} - 4ac = 0} \\ \\ \text{Putting \: the \: given \: values} \\ \tt{: \implies (k)^{2} - 4\times2 \times 2= 0 } \\ \\ \tt{: \implies \: {k}^{2} -16 = 0 } \\ \\ \tt{ : \implies \: ({k}^{2} - 4^{2}) = 0 } \\\\ \tt{: \implies (k+4)(k-4)= 0} \\ \\ \tt{: \implies k=4\:and\:-4} \\ \\ \green{\tt{: \implies k = \pm 4 }}$