document.write( "Question 1129941: Degree 4; zeros: 5+5i; -4 multiplicity 2 \n" ); document.write( "
Algebra.Com's Answer #746559 by greenestamps(13206) You can put this solution on YOUR website! \n" ); document.write( "The statement of the problem is not complete. Without the stated requirement that the polynomial have rational coefficients, the fourth root could be any complex number. \n" ); document.write( "Assuming rational coefficients, the four roots are -4, -4, 5+5i, and 5-5i. \n" ); document.write( "The quadratic polynomial with roots -4 and -4 is \n" ); document.write( " \n" ); document.write( "The quadratic polynomial with roots 5+5i and 5-5i is \n" ); document.write( " \n" ); document.write( "An alternative way to find the quadratic polynomial with roots 5+5i and 5-5i is to use the fact that the quadratic polynomial ax^2+bx+c has roots whose sum is -b/a and whose product is c/a. \n" ); document.write( "The sum of the roots 5+5i and 5-5i is 10; so the linear coefficient in the quadratic polynomial is -10. \n" ); document.write( "The product of the roots 5+5i and 5-5i is 25-25i^2 = 25+25 = 50; so the constant in the quadratic polynomial is 50. \n" ); document.write( "Then the quadratic polynomial with roots 5+5i and 5-5i is x^2-10x+50. \n" ); document.write( "Finally the polynomial with roots -4, -4, 5+5i and 5-5i is \n" ); document.write( " |