AP EAMCET201822 Apr 2018Morning ShiftMathematicsQuadratic EquationActual
If the sum of two roots of the equation x^3-2 p x^2+3 q x-4 r=0 is zero, then the value of r is
Options
- A3 p q 2
- B3 p q 4
- Cp q
- D2 p q
Correct answer
A. 3 p q 2
Step-by-step solution
Let the two roots of equation is m,-m . Now, sum of three roots =2 p Hence, third root will be 2 p . Now, m (-m)+m (2 p)+(-m) 2 p=3 q -m^2=3 q Now, m (-n) 2 p=4 r array rlrl & 3 q 2 p & =4 r & & r & = 3 p q 2 4 r= 3 p q 2 array