Multiple choice

The quadratic equation whose roots are 3 and – 1, is द्विघात समीकरण जिसके मूल 3 और – 1 हैं, है

  1. x2 – 4x + 3 = 0

  2. x2 – 2x – 3 = 0

  3. x2 + 2x – 3 = 0

  4. x2 + 4x + 3 = 0
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

To find a quadratic equation from given roots r1 and r2, use: x² - (r1 + r2)x + (r1 × r2) = 0. Here r1 = 3, r2 = -1. Sum = 3 + (-1) = 2. Product = 3 × (-1) = -3. Therefore the equation is x² - 2x - 3 = 0. Verify by factoring: x² - 2x - 3 = (x - 3)(x + 1), which gives roots 3 and -1. Option A would give roots 3 and 1; Option C gives -3 and 1; Option D gives -3 and -1.

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