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Solution of quadratic equations, Relation between roots and coefficients (only real roots to be considered). Practical problem on quadratic equations.

Find the values of k ε R subject to the following condition :
The sum of the roots of $3x^2 + kx - 2 = 0$ is 6.

Option:
A. 18
B. - 18
C. 12
D. 4
Answer: B . - 18

Justification:

Here, the sum of the roots is $α + β = (-k)/3 $
.`. $(-k)/3 = 6$.
.`. $k = - 18.$

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