Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NDA 2017
Exam
NDA
Year
2017
Subject
Mathematics
Chapter
Quadratic Equation

NDA 2017 · Mathematics · Quadratic Equation

If S=(x: x^2+1=0, x. is real ) , then S is

If S=(x:x2+1=0,xS=\left(x: x^2+1=0, x\right. is real )), then SS is

Options

  1. A{−1}\{-1\}
  2. B{0}\{0\}
  3. C{1}\{1\}
  4. Dan empty set

Correct answer

D. an empty set

Step-by-step solution

S={x:x2+1=0,x:5 real }x2+1=0⇒x2=−1⇒x=−1→ complex number \begin{aligned} & S=\left\{x: x^2+1=0, x: 5 \text{ real }\right\} \\ & x^2+1=0 \Rightarrow x^2=-1 \Rightarrow x=\sqrt{-1} \rightarrow \text{ complex number } \end{aligned} No real numbers. So, S is empty set
Practice Quadratic Equation on Quantrex Academy →

More from Quadratic Equation

For a given k , what is the minimum value of x^2+kx+k^2 ? NDA 2026If the highest degree coefficient is equal to 1 , then what is the total number of… NDA 2026Let α and β be the roots of the quadratic equation x^2-2bx+c^2=0 where b , c are positive… NDA 2026Consider the following statements : I. x + x+1=0 has two irrational roots. II. 5 x -x-4=0… NDA 2026For the following two (02) items: Let f(x) = ax^2 + bx + c be a quadratic polynomial such… NDA 2025For the following two (02) items: Let α and β be the roots of the quadratic equation x^2… NDA 2025For the following two (02) items: Let f(x) = ax^2 + bx + c be a quadratic polynomial such… NDA 2025If one root of the equation x^2 - kx + k = 0 exceeds the other by 2 3 , then which one of… NDA 2025For the following two (02) items: Let α and β be the roots of the quadratic equation x^2… NDA 2025If x = (1111)_2 , y = (1001)_2 and z = (110)_2 , then what is x^3 - y^3 - z^3 - 3xyz… NDA 2025If x^2 - x + 1 = 0 , then what is (x - (1)/(x))^2 + (x - (1)/(x))^4 + (x - (1)/(x))^8… NDA 2025If x + (5)/(y) = 4 and y + (5)/(x) = -4 , then what is (x + y) equal to? NDA 2025For the following two (02) items: Consider the equation abx^2 + bcx + ca = cax^2 + abx +… NDA 2025For the following two (02) items: Consider the equation abx^2 + bcx + ca = cax^2 + abx +… NDA 2025If n is a root of the equation x^2+p x+m=0 and m is a root of the equation x^2+p x+n=0… NDA 2024The roots of the equation 7 x^2-6 x+1=0 are α and β , where 2 α and 2 β are the angles of… NDA 2024 Full Quadratic Equation list Quadratic Equation JEE Maths PYQsJEE Mathematics PYQs All NDA PYQs