AP EAMCET2003MathematicsQuadratic Equation
If the sum of two of the roots of x^3+p x^2-q x+r=0 is zero, then p q is equal to
Options
- A-r
- Br
- C2 r
- D-2 r
Correct answer
A. -r
Step-by-step solution
Given that, x^3+p x^2-q x+r=0 (i) Let , , are roots of this equation + + =-p (ii) + + =-q (iii) and =-r (iv) Now, p q=( + + )( + + )=(0+ )( + ( + ))[ + =0 given ]= ( +0)= =-r