Q. Write a polynomial of least degree with real coefficients and with the root 1β6i.
Recognize Property of Complex Roots: Recognize that if a polynomial has real coefficients and a complex root, then the complex conjugate of that root must also be a root of the polynomial. The complex conjugate of 1β6i is 1+6i.
Write Root Factors: Write the factors associated with the roots 1β6i and 1+6i. The factors are (xβ(1β6i)) and (xβ(1+6i)).
Multiply Factors: Multiply the two factors to obtain the polynomial. We have: (xβ(1β6i))(xβ(1+6i))=(xβ1+6i)(xβ1β6i).
Expand Using FOIL Method: Use the FOIL method to expand the product of the two binomials:(xβ1+6i)(xβ1β6i)=x2βxβ6ixβx+1+6iβ6ix+6i+36i2.
Simplify Expression: Simplify the expression by combining like terms and using the fact that i2=β1: x2βxβ6ixβx+1+6iβ6ix+6iβ36=x2β2x+1β36=x2β2xβ35.
Verify Standard Form: Verify that the polynomial is in standard form with a leading coefficient of 1: The polynomial x2β2xβ35 is in standard form with a leading coefficient of 1.
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