KCET2010MathematicsQuadratic Equation
If a,-a, b are the roots of x³-5 x²-x+5=0 , then b is a root of
Options
- Ax²+3 x-20=0
- Bx²-5 x+10=0
- Cx²-3 x-10=0
- Dx²+5 x-30=0
Correct answer
C. x²-3 x-10=0
Step-by-step solution
Given, x³-5 x²-x+5=0 Hare, roots (a, - a, b). Sum of the roots =a-a+b=5 b=5 and b=5 satisfies the equation ie, aligned f(x) & x²-3 x-10=0 f(5) & (5)²-3(5)-10 &=25-15-10 &=0 aligned So, (b) is the roots equation x²-3 x-10=0 .