Question

What will be the value/values of 'p' ,if the quadratic equation $2x^2+px+2=0$ has two equal real roots?

• A. 2
• B. -2
• C. 4
• D. -4

Answer 1

Answer: (C), (D)

The correct options are
C 4
D -4

Since the equation $2x^2+px+2=0$ has 2 equal real roots, its discriminant will be zero.
When you compare $2x^2+px+2=0$ to the standard form $a{x}^2+bx+c=0$
we get , a =2,b =p and c = 2
$\Rightarrow D=b^2-4ac=p^2-4\times 2\times 2=0$
$\Rightarrow p^2-16=0$
$\Rightarrow p^2=16$
$\Rightarrow p=+4or-4$