CAT 1995 — QA Question 26
Forming a Quadratic Equation and Relation between roots and coefficientsEasy
One root of x2 + kx – 8 = 0 is square of the other. Then the value of k is
Answer & solution
Correct answer: -2
- A
2
- B
8
- C
-8
-2
Solution
If the roots are a and a2, the product of roots = a3 = –8.
∴ a = –2.
Hence, sum of the roots = -k = (a + a2) = (–2 + 4) = 2.
∴ k = -2.
Hence, option (d).