JEE Exam  >  JEE Questions  >  Let p,q € {1,2,3,4}.Find the number of the eq... Start Learning for Free
Let p,q € {1,2,3,4}.Find the number of the equations of the form of px2 qx 1, which have real roots.?
Most Upvoted Answer
Let p,q € {1,2,3,4}.Find the number of the equations of the form of px...
Since real roots...∆>=0
so here ∆=q^2-4p
since discriminant is greater than or equal to zero
=>..... q^2-4p>=0
=>....q^2>=4p
=>.....now the equation satisfies... when p=1and q=2
we can consider.. when p=1 then q={2,3,4}
when p=2 then q={3,4}
when p=3 then q={4}
when p=4 then q={4}
so the solutions (p q) are (1 2) (1 3) (1 4) (2 3) (2 4) (3 4) (4 4).....total 7
Community Answer
Let p,q € {1,2,3,4}.Find the number of the equations of the form of px...
Number of Equations with Real Roots

To find the number of equations of the form px^2 + qx + 1 with real roots, we need to analyze the discriminant of the quadratic equation.

Quadratic Equation
A quadratic equation has the general form ax^2 + bx + c = 0, where a, b, and c are constants.

Discriminant
The discriminant of a quadratic equation is given by the formula Δ = b^2 - 4ac. It determines the nature of the roots of the equation.

Real Roots
For a quadratic equation to have real roots, the discriminant must be greater than or equal to zero, i.e., Δ ≥ 0.

Analysis

Let's consider each value of p and q from the set {1, 2, 3, 4} and analyze the discriminant to determine the number of equations with real roots.

Case 1: p = 1
For p = 1, the quadratic equation becomes x^2 + qx + 1 = 0.

Substituting the values of q and analyzing the discriminant:
- For q = 1, Δ = 1 - 4(1)(1) = -3 (No real roots)
- For q = 2, Δ = 4 - 4(1)(1) = 0 (One real root)
- For q = 3, Δ = 9 - 4(1)(1) = 5 (Two real roots)
- For q = 4, Δ = 16 - 4(1)(1) = 12 (Two real roots)

Thus, when p = 1, there are two values of q (3 and 4) that result in equations with real roots.

Case 2: p = 2
For p = 2, the quadratic equation becomes 2x^2 + qx + 1 = 0.

Substituting the values of q and analyzing the discriminant:
- For q = 1, Δ = 1 - 4(2)(1) = -7 (No real roots)
- For q = 2, Δ = 4 - 4(2)(1) = -4 (No real roots)
- For q = 3, Δ = 9 - 4(2)(1) = 1 (One real root)
- For q = 4, Δ = 16 - 4(2)(1) = 8 (Two real roots)

Thus, when p = 2, there are two values of q (3 and 4) that result in equations with real roots.

Case 3: p = 3
For p = 3, the quadratic equation becomes 3x^2 + qx + 1 = 0.

Substituting the values of q and analyzing the discriminant:
- For q = 1, Δ = 1 - 4(3)(1) = -11 (No real roots)
- For q = 2, Δ = 4 - 4(3)(1) = -8 (No real roots)
- For q = 3, Δ = 9 - 4(3)(1) = -3 (
Explore Courses for JEE exam
Let p,q € {1,2,3,4}.Find the number of the equations of the form of px2 qx 1, which have real roots.?
Question Description
Let p,q € {1,2,3,4}.Find the number of the equations of the form of px2 qx 1, which have real roots.? for JEE 2024 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about Let p,q € {1,2,3,4}.Find the number of the equations of the form of px2 qx 1, which have real roots.? covers all topics & solutions for JEE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Let p,q € {1,2,3,4}.Find the number of the equations of the form of px2 qx 1, which have real roots.?.
Solutions for Let p,q € {1,2,3,4}.Find the number of the equations of the form of px2 qx 1, which have real roots.? in English & in Hindi are available as part of our courses for JEE. Download more important topics, notes, lectures and mock test series for JEE Exam by signing up for free.
Here you can find the meaning of Let p,q € {1,2,3,4}.Find the number of the equations of the form of px2 qx 1, which have real roots.? defined & explained in the simplest way possible. Besides giving the explanation of Let p,q € {1,2,3,4}.Find the number of the equations of the form of px2 qx 1, which have real roots.?, a detailed solution for Let p,q € {1,2,3,4}.Find the number of the equations of the form of px2 qx 1, which have real roots.? has been provided alongside types of Let p,q € {1,2,3,4}.Find the number of the equations of the form of px2 qx 1, which have real roots.? theory, EduRev gives you an ample number of questions to practice Let p,q € {1,2,3,4}.Find the number of the equations of the form of px2 qx 1, which have real roots.? tests, examples and also practice JEE tests.
Explore Courses for JEE exam

Top Courses for JEE

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev