Find the quadratic equations whose roots are the reciprocals of the roots of 2x2 + 5x + 3 = 0?
Correct answer: B. 3x2 + 5x + 2 = 0
- A. 3x2 + 5x - 2 = 0
- B. 3x2 + 5x + 2 = 0
- C. 3x2 - 5x + 2 = 0
- D. 3x2 - 5x - 2 = 0
Explanation
If r is a root of 2r² + 5r + 3 = 0 and z = 1/r, substitute r = 1/z: 2/z² + 5/z + 3 = 0. Multiplying by z² gives 3z² + 5z + 2 = 0, so option b has the reciprocal roots. The likely mistake is choosing option a by changing the constant term incorrectly instead of reversing the coefficients.
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