English

Assertion (A): The discriminant of the quadratic equation x^2 + 2sqrt(2)x + 1 = 0 is less than zero. Reason (R): The discriminant of the quadratic equation ax^2 + bx + c = 0 is sqrt(b^2 – 4ac).

Advertisements
Advertisements

Question

Assertion (A): The discriminant of the quadratic equation `x^2 + 2sqrt(2)x + 1 = 0` is less than zero.

Reason (R): The discriminant of the quadratic equation ax2 + bx + c = 0 is `sqrt(b^2 - 4ac)`.

Options

  • A is true, R is false

  • A is false, R is true

  • Both A and R are true

  • Both A and R are false

MCQ
Assertion and Reasoning
Advertisements

Solution

Both A and R are false

Explanation:

For `x^2 + 2sqrt(2)x + 1 = 0`,

a = 1, b = `2sqrt(2)`, c = 1, 

So, discriminant Δ = b2 – 4ac 

= `(2sqrt(2))^2 - 4(1)(1)`

= 8 – 4

= 4 (> 0) 

Thus, A (Δ < 0) is false.

R is false because the discriminant is the expression b2 – 4ac itself; the quadratic formula uses `sqrt((b^2 - 4ac)`, but the discriminant is not the square root.

shaalaa.com
  Is there an error in this question or solution?
Chapter 5: Quadratic Equation - EXERCISE 5C [Page 65]

APPEARS IN

R.S. Aggarwal Mathematics [English] Class 10 ICSE
Chapter 5 Quadratic Equation
EXERCISE 5C | Q 1. | Page 65
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×