Multiple choice

The condition that the roots of the equation px2 + qx + r = 0 are the reciprocals of the roots of equation ax2 + bx + c = 0 is

  1. acq2 = b2pr

  2. ac = pr

  3. b2 = q2

  4. b2ac = q2pr
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A Correct answer
Explanation

If roots of px^2 + qx + r = 0 are reciprocals of ax^2 + bx + c = 0, then the coefficients must be reversed. Thus, p=c, q=b, r=a. Substituting these into the original equation, we get cx^2 + bx + a = 0. Comparing the coefficients of the two equations, we find the condition acq^2 = b^2pr.

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