If the equation, x 2 + bx + 45 = 0 (b Î R) has conugate complex roots and they satisfy |z + l| = 2 10 , then:

Question:

If the equation, $x^{2}+b x+45=0(b \in R)$ has conjugate complex roots and they satisfy $|z+1|=2 \sqrt{10}$, then:

  1. $b^{2}-b=30$

  2. $b^{2}+b=72$

  3. $b^{2}-b=42$

  4. $b^{2}+b=12$

Correct Option: 1

JEE Main Previous Year 1 Question of JEE Main from Mathematics Complex Numbers and Quadratic Equations chapter.
JEE Main Previous Year Jan. 8, 2020 (I)

Solution:

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