Question

Q:-16- The factors form of x2+2x-4 is *
O (x+2/2) (x-v2)
O (X-2V2) (x+v2)
O (x-2/2) (x-v2)
O None of these​

Answer 1

$\bf{\underline{\underline{Question:-}}}$

• Find the Factor from $\sf x^2 + 2x-4$

$\bf{\underline{\underline{Given\: Polynomial:-}}}$

• $\sf x^2 + 2x-4$

$\bf{\underline{\underline{Solution:-}}}$

$\bf{\underline{\underline{Using\: Completing\: Square\: Method:-}}}$

$\sf :→ x^2 + 2x-4$

$\sf :→ x^2+2x + 1^2 = 4+1^2$

$\sf :→ x^2 + 2x + 1 = 4 + 1$

$\sf :→ ( x + 1)^2 = 5$

$\bf{\underline{\underline{Taking\: Square\:root\:on\:both\:side:-}}}$

$\sf :→ \sqrt{(x+1)^2} = \sqrt{5}$

$\sf :→ x + 1 = 1 + \sqrt{5}$

$\sf :→ x = -1 ± \sqrt{5}$

$\bf{\underline{\underline{Hence:-}}}$

• Factor = $\sf :→ x = -1 ± \sqrt{5}$

|| Option (d) is right answer ||