Subject
গণিত
Topic
Algebra
Real-coefficient polynomial with roots 2, 1 ± i; write the monic cubic.
Real-coefficient polynomial with roots 2, 1 ± i; write the monic cubic.
ক)
x3− 4x2+ 6x − 4খ)
x3− 4x2+ 5x − 2গ)
x3− 3x2+ 4x − 2ঘ)
x3− 2x2+ 2x − 2Explanation
We are given roots and asked for the monic cubic polynomial with real coefficients. Since complex roots come in conjugate pairs for real-coefficient polynomials, the quadratic factor from is Multiplying by the linear factor for the root gives the cubic: Expand: So the monic cubic is , which matches Option 1.Related questions
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