Multiple choice

If roots of the equation lx^2 + mx - 2 = 0 are reciprocal of each other, then

  1. l = 2

  2. l=-2

  3. m = 2

  4. m = - 2
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B Correct answer
Explanation

If roots are reciprocals, their product is 1. For lx^2 + mx - 2 = 0, the product of roots is c/a = -2/l. Setting -2/l = 1 gives l = -2.

AI explanation

For a quadratic equation lx squared plus mx minus 2 equals 0, the product of the roots is given by the constant term divided by the leading coefficient, which is negative 2 divided by l. Since the roots are reciprocals of each other, their product must equal 1. Setting negative 2 divided by l equal to 1 gives l equals negative 2.

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