document.write( "Question 64642: I am struggling with some problems. Could someone please help me!!!!\r
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document.write( "1. Find a third degree polynomial with real coefficents and with real zeros 2 and 4+i. Write your answer in ax^3+bx^2+cx+d form. I have x^3-10x^2+33x-34 is that correct and is there anything else I should do to it?\r
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document.write( "2. Use Decartes' Rule of Sign to find the number of possible number of positive zeros and the possible number of negative zeros of Q(x)= x^4-2x^3+4x^2-3x-2. I am completely stuck on this one and don't even know where to start.\r
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document.write( "Thank you for your help!!!! \n" );
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Algebra.Com's Answer #46237 by venugopalramana(3286)![]() ![]() You can put this solution on YOUR website! I am struggling with some problems. Could someone please help me!!!! \n" ); document.write( "1. Find a third degree polynomial with real coefficents and with real zeros 2 and 4+i. Write your answer in ax^3+bx^2+cx+d form. I have x^3-10x^2+33x-34 is that correct and is there anything else I should do to it? \n" ); document.write( "SINCE COEFFICIENTS ARE REAL ,THEN COMPLEX ROOTS SHOULD BE IN CONJUGATES. \n" ); document.write( "HENCE IF 4+i IS A ROOT,THEN 4-i SHOULD ALSO BE A ROOT. \n" ); document.write( "HENCE THE 3 ROOTS ARE 2,4+i,4-i.HENCE POLYNOMIAL IS \n" ); document.write( "(X-2)[X-(4+i)][X-(4-i)]=0 \n" ); document.write( "(X-2)[(X-4)^2-i^2]=0 \n" ); document.write( "(X-2)[X^2-8X+16+1]=0 \n" ); document.write( "X^3 - 8X^2+17X-2X^2+16X-34=0 \n" ); document.write( "X^3-10X^2+33X-34=0...........OK\r \n" ); document.write( "\n" ); document.write( "2. Use Decartes' Rule of Sign to find the number of possible number of positive zeros and the possible number of negative zeros of Q(x)= x^4-2x^3+4x^2-3x-2. I am completely stuck on this one and don't even know where to start. \n" ); document.write( "THE RULE SAYS.FIND CHANGES IN SIGN OF COEFFICIENTS OF THE TERMS OF THE FUNCTION WHEN WRITTEN IN A DESCENDING ORDER. \n" ); document.write( "WE ALREADY HAVE THE FUNCTION IN DECENDING ORDER. \n" ); document.write( "WE HAVE HERE ONE CHANGE FROM +1 TO -2 \n" ); document.write( "2 ND CHANGE FROM -2 TO +4 \n" ); document.write( "3 RD. CHANGE FROM +4 TO -3 \n" ); document.write( "SO THE NUMBER OF CHANGES =3 = MAXIMUM NUMBER OF POSITIVE RATIONAL ROOTS.THEY COULD BE 3 OR 3-2 = 1.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Thank you for your help!!!! \n" ); document.write( " \n" ); document.write( " |