If 2 is a root of the quadratic equation 2x 2 - kx + 1 = 0, then the value of k is 1. 9 2. -9 3. 4.

If 2 is a root of the quadratic equation 2x 2 - kx + 1 = 0, then it will satisfy the equation. ⇒ 2(2) 2 - 2(k) + 1 = 0 ⇒ 2(4) - 2k + 1 = 0 ⇒ 8 + 1 - 2k = 0 ⇒ 2k = 9 ⇒ k = . Hence, Option 3 is the correct option.

Mathematics

If 2 is a root of the quadratic equation 2x² - kx + 1 = 0, then the value of k is
9
-9
$\dfrac{9}{2}$
$-\dfrac{9}{2}$

Quadratic Equations

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Answer

If 2 is a root of the quadratic equation 2x² - kx + 1 = 0, then it will satisfy the equation.

⇒ 2(2)² - 2(k) + 1 = 0

⇒ 2(4) - 2k + 1 = 0

⇒ 8 + 1 - 2k = 0

⇒ 2k = 9

⇒ k = $\dfrac{9}{2}$ .

Hence, Option 3 is the correct option.

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Mathematics

If 2 is a root of the quadratic equation 2x² - kx + 1 = 0, then the value of k is
9
-9
$\dfrac{9}{2}$
$-\dfrac{9}{2}$

Quadratic Equations

Answer

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