Question

For what value of k, "3" is a root of equation 2x2 +x+ k=0

Answer 1

   

$p(x)=2x^2+x+k=0 \\ \\ \\ p(3)=2(3)^2+3+k=0 \\ \\ p(3)=2 \times 9+3+k=0 \\ \\ p(3)=18+3+k=0 \\ \\ p(3)=21+k=0 \\ \\ \\ 21+k=0 \\ \\ k=\bold{-21} \\ \\ \\ Thank you. :-)) \\ \\ \\ \mathfrak{\#adithyasajeevan}$

   

Answer 2

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