document.write( "Question 199208: Somehow my jamielee90@ymail.com address doesnt seem to be working since I never seem to recieve a msg's from this site, on that account, so I asked a friend to make me an account on his, hope it goes through now =/\r
\n" ); document.write( "\n" ); document.write( "Ok so to the real problem, I dont get how to solve these problems, could someone help me out here?
\n" ); document.write( "1)Find a quadratic equation with roots (4+i) and (4-i).
\n" ); document.write( "2)Find the irrational roots of x^3-4x^2+2x+1=0 (I should also use the quadratic formula to solve it)
\n" ); document.write( "3) x^3-2x^2+x-3=0 what are the possible rational roots?
\n" ); document.write( "As you might see I am not too good with roots, I never really have been =(
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Algebra.Com's Answer #149702 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"x=4%2Bi\" or \"x=4-i\" Start with the given solutions.\r
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\n" ); document.write( "\n" ); document.write( "\"x-4=i\" or \"x-4=-i\" Subtract 4 from both sides (for each equation).\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-4%29%5E2=i%5E2\" or \"%28x-4%29%5E2=%28-i%29%5E2\" Square both sides\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-4%29%5E2=-1\" or \"%28x-4%29%5E2=-1\" Square i to get -1 and square -i to get -1\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-4%29%5E2%2B1=0\" or \"%28x-4%29%5E2%2B1=0\" Add 1 to both sides.\r
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\n" ); document.write( "\n" ); document.write( "Since the equations are the same, we can focus on one equation:\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-4%29%5E2%2B1=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-8x%2B16%2B1=0\" FOIL\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-8x%2B17=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So the quadratic with the roots 4+i and 4-i is \"y=x%5E2-8x%2B17\"\r
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\n" ); document.write( "\n" ); document.write( "# 2\r
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\n" ); document.write( "\n" ); document.write( "First, let's find the possible rational zeros\r
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\n" ); document.write( "\n" ); document.write( "Any rational zero can be found through this equation\r
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\n" ); document.write( "\n" ); document.write( " where p and q are the factors of the last and first coefficients\r
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\n" ); document.write( "\n" ); document.write( "So let's list the factors of 1 (the last coefficient):\r
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\n" ); document.write( "\n" ); document.write( "Now let's list the factors of 1 (the first coefficient):\r
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\n" ); document.write( "\n" ); document.write( "Now let's divide each factor of the last coefficient by each factor of the first coefficient\r
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\n" ); document.write( "\n" ); document.write( "Now simplify\r
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\n" ); document.write( "\n" ); document.write( "These are all the distinct rational zeros of the function that could occur\r
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\n" ); document.write( "\n" ); document.write( "Let's see if the possible zero \"1\" is really a root for the function \"x%5E3-4x%5E2%2B2x%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "So let's make the synthetic division table for the function \"x%5E3-4x%5E2%2B2x%2B1\" given the possible zero \"1\":\r
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1|1-421
| 1-3-1
1-3-10
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\n" ); document.write( "\n" ); document.write( "Since the remainder \"0\" (the right most entry in the last row) is equal to zero, this means that \"1\" is a zero of \"x%5E3-4x%5E2%2B2x%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "Take note that the first three values in the bottom row are 1, -3, and -1. So this means that\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3-4x%5E2%2B2x%2B1=%28x-1%29%28x%5E2-3x-1%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now all we need to do is solve \"x%5E2-3x-1=0\" to find the next two zeros:\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic in the form of \"Ax%5E2%2BBx%2BC\" where \"A=1\", \"B=-3\", and \"C=-1\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for \"x\":\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%28-3%29+%2B-+sqrt%28+%28-3%29%5E2-4%281%29%28-1%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=-3\", and \"C=-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+%28-3%29%5E2-4%281%29%28-1%29+%29%29%2F%282%281%29%29\" Negate \"-3\" to get \"3\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+9-4%281%29%28-1%29+%29%29%2F%282%281%29%29\" Square \"-3\" to get \"9\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+9--4+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-1%29\" to get \"-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+9%2B4+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%289--4%29\" as \"sqrt%289%2B4%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+13+%29%29%2F%282%281%29%29\" Add \"9\" to \"4\" to get \"13\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+13+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283%2Bsqrt%2813%29%29%2F%282%29\" or \"x+=+%283-sqrt%2813%29%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the next two zeros are \"x+=+%283%2Bsqrt%2813%29%29%2F%282%29\" or \"x+=+%283-sqrt%2813%29%29%2F%282%29\" \r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the three roots are \"x=1\", \"x+=+%283%2Bsqrt%2813%29%29%2F%282%29\" or \"x+=+%283-sqrt%2813%29%29%2F%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "where the irrational roots are \"x+=+%283%2Bsqrt%2813%29%29%2F%282%29\" and \"x+=+%283-sqrt%2813%29%29%2F%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "# 3\r
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\n" ); document.write( "\n" ); document.write( "Any rational zero can be found through this equation\r
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\n" ); document.write( "\n" ); document.write( " where p and q are the factors of the last and first coefficients\r
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\n" ); document.write( "\n" ); document.write( "So let's list the factors of -3 (the last coefficient):\r
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\n" ); document.write( "\n" ); document.write( "Now let's list the factors of 1 (the first coefficient):\r
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\n" ); document.write( "\n" ); document.write( "Now let's divide each factor of the last coefficient by each factor of the first coefficient\r
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\n" ); document.write( "\n" ); document.write( "Now simplify\r
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\n" ); document.write( "\n" ); document.write( "These are all the distinct rational zeros of the function that could occur\r
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