document.write( "Question 254301: I actually have three questions. Two of the same type. Different numbers of roots, and I'm not even sure this is the right heading, but I couldn't find one that fit better, if you could help that would be great. If they're the same thing in the end, one being solved is fine, I just need a better explanation than the notes I was given for my online class. :(. The third question has imaginary numbers in it, and after a failed, and very irritating attempt I thought I would seek assistance.\r
\n" ); document.write( "\n" ); document.write( "1. Determine all roots of P(x) = 3x^4+5x^3-9x^2-10x+8.\r
\n" ); document.write( "\n" ); document.write( "2. Determine all the roots of P(x) = 3x^5+5x^4+10x^3+14x^2+3x-3.\r
\n" ); document.write( "\n" ); document.write( "3. Determine a polynomial P(x) with real coefficients and of degree 5 for which three of its roots are x= -1, x = 1+2i and x= -3i.\r
\n" ); document.write( "\n" ); document.write( "Thank you!
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Algebra.Com's Answer #186670 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
1. Determine all roots of P(x) = 3x^4+5x^3-9x^2-10x+8.
\n" ); document.write( "I had to graph it to find zeroes:
\n" ); document.write( "x = 1.6371972...
\n" ); document.write( "x = -2.409123
\n" ); document.write( "The other two roots seem to be complex.
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\n" ); document.write( "2. Determine all the roots of P(x) = 3x^5+5x^4+10x^3+14x^2+3x-3.
\n" ); document.write( "x = 1/3 is the only Real root
\n" ); document.write( "The other 4 roots seem to be complex.
\n" ); document.write( "---------------------------------------------
\n" ); document.write( "3. Determine a polynomial P(x) with real coefficients and of degree 5 for which three of its roots are x= -1, x = 1+2i and x= -3i.
\n" ); document.write( "----
\n" ); document.write( "Since the coefficients are Real x = 1-2i and x = +3i
\n" ); document.write( "are also roots
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\n" ); document.write( "P(x) = (x+1)((x-1)-2i)((x-1)+2i)(x-3i)(x+3i)
\n" ); document.write( "---
\n" ); document.write( "P(x) = (x+1)((x-1)^2+4)(x^2+9)
\n" ); document.write( "---
\n" ); document.write( "P(x) = (x+1)(x^2-2x+5)(x^2+9)
\n" ); document.write( "=====================================
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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