document.write( "Question 1191999: Form a fifth-degree polynomial function with real coefficients such that 5i, 1-3i, and -3 are zeros and f(0)=1500 \n" ); document.write( "
Algebra.Com's Answer #823880 by Edwin McCravy(20062)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Instead of doing your problem for you, I'm going to do \r\n" );
document.write( "one exactly like it instead, step by step.  Here's the one I'm \r\n" );
document.write( "going to do. Use it as a model for yours.

\n" ); document.write( "Form a fifth-degree polynomial function with real coefficients
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document.write( "If a polynomial with real coefficients has a complex imaginary zero,\r\n" );
document.write( "its conjugate is also a zero.\r\n" );
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document.write( "Since 6i is a zero, so is -6i.\r\n" );
document.write( "Since 1-4i is a zero, so is 1+4i.\r\n" );
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document.write( "x-6i, x-(-6i), x-(1-4i), x-(1+4i), x-(-4) are all factors. Simplifying them:\r\n" );
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document.write( "x-6i, x+6i, x-1+4i, x-1-4i, x+4\r\n" );
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document.write( "So f(x) must be some constant \"a\" times the product of those factors:\r\n" );
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document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\r\n" );
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document.write( "Multiply that out:\r\n" );
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document.write( "It makes it a little easier to group the real parts of conjugates:\r\n" );
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document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\r\n" );
document.write( " \r\n" );
document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\"a%28x%5E2-36i%5E2%29%28%28x-1%29%5E2-16i%5E2%29%0D%0A%0D%0A%28x%2B4%5E%22%22%29\"\r\n" );
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document.write( "Since i2 = -1\r\n" );
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document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\"a%28x%5E2%2B36%29%28%28x-1%29%5E2%2B16%29%0D%0A%0D%0A%28x%2B4%5E%22%22%29\"\r\n" );
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document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\"a%28x%5E2%2B36%29%28%28x%5E2-2x%2B1%29%5E%22%22%2B16%29%0D%0A%0D%0A%28x%2B4%5E%22%22%29\"\r\n" );
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document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\"a%28x%5E2%2B36%29%28x%5E2-2x%2B17%29%0D%0A%0D%0A%28x%2B4%5E%22%22%29\"\r\n" );
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document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\"a%28x%5E4-2x%5E3%2B17x%5E2%2B36x%5E2-72x%2B612%29%28x%2B4%5E%22%22%29\"\r\n" );
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document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\"a%28x%5E4-2x%5E3%2B53x%5E2-72x%2B612%29%28x%2B4%5E%22%22%29\"\r\n" );
document.write( "\r\n" );
document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\"a%28x%5E5-2x%5E4%2B53x%5E3-72x%5E2%2B612x%2B4x%5E4-8x%5E3%2B212x%5E2-288x%2B2448%29\"\r\n" );
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document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\"a%28x%5E5%2B2x%5E4%2B45x%5E3%2B140x%5E2%2B324x%2B2448%29\"\r\n" );
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document.write( "Since f(0)=7344,\r\n" );
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document.write( "\"%22f%280%29%22\"\"%22%22=%22%22\"\"a%280%5E5%2B2%280%29%5E4%2B45%280%29%5E3%2B140%280%29%5E2%2B324%280%29%2B2448%29\"\r\n" );
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document.write( "\"7344\"\"%22%22=%22%22\"\"2448a\"\r\n" );
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document.write( "\"3\"\"%22%22=%22%22\"\"a\"\r\n" );
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document.write( "So\r\n" );
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document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\"3%28x%5E5%2B2x%5E4%2B45x%5E3%2B140x%5E2%2B324x%2B2448%29\"\r\n" );
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document.write( "\"%22f%28x%29%22\"\"%22%22=%22%22\"\"3x%5E5%2B6x%5E4%2B135x%5E3%2B420x%5E2%2B972x%2B7344%29\"\r\n" );
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document.write( "Edwin
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