If x = 3 is a root of the quadratic equation x 2 - 2kx - 6 = 0, then the value of k is : 1. 1 2. 2 3. 4.

Given, x = 3 is a root of the quadratic equation x 2 - 2kx - 6 = 0, so it will satisfy it : ⇒ (3) 2 - 2k(3) - 6 = 0 ⇒ 9 - 6k - 6 = 0 ⇒ 3 - 6k = 0 ⇒ 6k = 3 ⇒ k = . Hence, Option 3 is the correct option.

Mathematics

If x = 3 is a root of the quadratic equation x² - 2kx - 6 = 0, then the value of k is :
1
2
$\dfrac{1}{2}$
$\dfrac{1}{3}$

Quadratic Equations

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Answer

Given,

x = 3 is a root of the quadratic equation x² - 2kx - 6 = 0, so it will satisfy it :

⇒ (3)² - 2k(3) - 6 = 0

⇒ 9 - 6k - 6 = 0

⇒ 3 - 6k = 0

⇒ 6k = 3

⇒ k = $\dfrac{3}{6} = \dfrac{1}{2}$ .

Hence, Option 3 is the correct option.

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Mathematics

If x = 3 is a root of the quadratic equation x² - 2kx - 6 = 0, then the value of k is :
1
2
$\dfrac{1}{2}$
$\dfrac{1}{3}$

Quadratic Equations

Answer

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