InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
Let a, b, c, d be real numbers between – 5 and 5 such that `|a|=sqrt(4-sqrt(5-a)),|b|=sqrt(4+sqrt(5-b))`, `|c|=sqrt(4-sqrt(5+c)),|d|=sqrt(4+sqrt(5+d)),`. Then the product abcd isA. 11B. -11C. 121D. -121 |
|
Answer» Correct Answer - A `"Given "|a| =sqrt(4-sqrt(5-a))` `"squaring"` `a^(2)=4-sqrt(5-a)` `rArra^(4)+16-8a^(2)=5-a` `rArra^(4)-8a^(2)+a+11=0` Similarly squaring other given equations `&` solving we can say that a,b,-c,-d are roots `" of "x^(4)-8x^(2)+x+11=0` `therefore "product of roots "` ab(-c)(-d)=11 abcd=11 |
|