CA Foundation P3 · Chapter 2 · Question 5 of 9
The quadratic equation whose roots are 3 + √2 and 3 − √2 is:
Test yourself: pick an answer
Reveal answer & explanation
Correct answer: B) x² − 6x + 7 = 0
Explanation
Sum of roots = 6 and product = (3 + √2)(3 − √2) = 9 − 2 = 7. The equation is x² − (sum)x + product = 0, i.e. x² − 6x + 7 = 0. Using 9 + 2 for the product gives x² − 6x + 11 = 0.
More Equations MCQs
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- Q8One root of x³ − 6x² + 11x − 6 = 0 is 1. The other two roots are:
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- Q1The solution of the equation 5x − 7 = 3x + 11 is:
- Q2The roots of the equation x² − 11x + 28 = 0 are: