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Question 6 - Quadaratic equation - Chapter 4 Class 11 Complex Numbers
Last updated at August 17, 2026 by Teachoo
Chapter 4 Class 11 Complex Numbers
Concept wise
-
Quadaratic equation
- Two complex numbers equal
- Convert to a + ib form
- Identities (square, cube of 2 complex numbers)
- Division
- Power of i(odd and even)
- Conjugate
- Modulus,argument
- Polar representation
- Proof- Replacing iota with -iota
- Proof- Taking general complex numbers
- Proof- Solving
- Proof- Using modulus conjugate property (Pg 102)
Transcript
Ex5.3, 6 Solve the equation 𝑥2 – 𝑥 + 2 = 0 x2 – x + 2 = 0 The above equation is of the form 𝑎𝑥2 + 𝑏𝑥 + 𝑐 = 0 Where a = 1 , b = –1 , c = 2 x = (−𝑏 ± √( 𝑏^2 −4𝑎𝑐 ))/2𝑎 x = (−(−1) ± √((−1)^2 − 4 × 1 × 2))/(2 × 1) = (1 ± √(1−8))/2 = (1 ± √(−7))/2 = (1 ± √(−1 × 7))/2 = (1± √(−1) ×√7)/2 = (1 ± √7 𝑖)/2 Thus, 𝑥 = (1 ± √7 𝑖)/2
