InterviewSolution
Saved Bookmarks
| 1. |
Let p, q, r `in` R and `r gt p gt 0`. If the quadratic equation `px^(2) + qx + r = 0` has two complex roots `alpha and beta`, then `|alpha|+|beta|`, isA. less than 2 but not equat to 1B. equal to 2C. equal to 1D. greater than 2 |
|
Answer» Correct Answer - D Since `alpha and beta` are complex conjugate of each other. `therefore" "alpha = bar(beta) and , bar(alpha) = beta rArr |alpha| = |beta|` Now, `alpha = bar(beta) rArr alpha beta = bar(beta)beta rArr alpha beta = |beta|^(2)` Now, `alpha beta = (r)/(p) rArr |alpha|^(2) = |beta|^(2) = (r)/(p) gt 1 rArr |alpha| = |beta| gt 1` Hence, `|alpha|+|beta| gt 2`. |
|