Let . if is a root of the quadratic equation, , then:
- (A)
- (B)
- (C)✓ Correct
- (D)
Answer: (C)
Solution
A quadratic with real coefficients having as a root takes its conjugate as the other root, so the sum is and the product is , giving and . The square of the difference of the roots equals the discriminant, , hence .
JEE Main · 2019 · 09 Apr 2019 · Shift 1 · Single correct option