arrow
arrow
arrow
If the roots of quadratic equation(2−p)x2+2px−(p+1)=0 (2-p)x^2+2px-(p+1)=0(2−p)x2+2px−(p+1)=0​ are equal, then the value of p is:
Question

If the roots of quadratic equation(2p)x2+2px(p+1)=0 (2-p)x^2+2px-(p+1)=0​ are equal, then the value of p is:

A.

2

B.

-2

C.

1

D.

-1

Correct option is B

Given:

Equation

(2p)x2+2px(p+1)=0 (2-p)x^2+2px-(p+1)=0

Concept Used:

The discriminant Δ for a quadratic equation    ax2+bx+c=0ax 2 ​+ b x + c = 0  is  given by:

Δ=b24acΔ = b 2 − 4 a c

For the roots to be equal, the discriminant must be zero: Δ=0\Delta = 0​​

Solution:

From the Equation 

(2p)x2+2px(p+1)=0 (2-p)x^2+2px-(p+1)=0

​Substitute the values of a , b and c , then discriminant

Δ=(2p)24(2p)((p+1))Δ=(2p) 2 ​−4(2−p)(−(p+1))

Δ=4p2+4(2p)(p+1)\Delta = 4p^2 + 4(2 - p)(p + 1)

Δ=4p2+4(p2+p+2)\Delta = 4p^2 + 4(-p^2 + p + 2)

Δ = 4p + 8

As Δ = 0, So 4p = −8

Free Tests

Free
Must Attempt

CBT-1 Full Mock Test 1

languageIcon English
  • pdpQsnIcon100 Questions
  • pdpsheetsIcon100 Marks
  • timerIcon90 Mins
languageIcon English
Free
Must Attempt

RRB NTPC Graduate Level PYP (Held on 5 Jun 2025 S1)

languageIcon English
  • pdpQsnIcon100 Questions
  • pdpsheetsIcon100 Marks
  • timerIcon90 Mins
languageIcon English
Free
Must Attempt

RRB NTPC UG Level PYP (Held on 7 Aug 2025 S1)

languageIcon English
  • pdpQsnIcon100 Questions
  • pdpsheetsIcon100 Marks
  • timerIcon90 Mins
languageIcon English
test-prime-package

Access ‘RRB Group D’ Mock Tests with

  • 60000+ Mocks and Previous Year Papers
  • Unlimited Re-Attempts
  • Personalised Report Card
  • 500% Refund on Final Selection
  • Largest Community
students-icon
368k+ students have already unlocked exclusive benefits with Test Prime!
Our Plans
Monthsup-arrow