The number of roots common between the two equations x^3 + 3x^2 + 4x + 5 = 0
The number of roots common between the two equations x3 + 3x2 + 4x + 5 = 0 and x3 + 2x2 + 7x + 3 = 0 is
- 0
- 1
- 2
- 3
Answer
Let α is the common root.
α3 + 3α2 + 4α + 5 = 0
α3 + 2α2 + 7α + 3 = 0
Subtracting one equation from another,
α2 - 3α + 2 = 0
α = 2; α = 1
But the above values of α do not satisfy any of the equations. Thus, no root is common.
The correct option is A.