document.write( "Question 1010032: n=3
\n" ); document.write( "2 and 2i are zeros
\n" ); document.write( "f(-1)=-15
\n" ); document.write( "What does f(x) =
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Algebra.Com's Answer #625500 by MathLover1(20850)\"\" \"About 
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\"+n=3\"=> degree \"3\"
\n" ); document.write( "\"x%5B1%5D=2\" and \"x%5B2%5D=2i\" are zeros
\n" ); document.write( "if \"x%5B2%5D=2i\" is zero, then \"x%5B3%5D=+-2i\" is zero too, complex zeros always come in pairs
\n" ); document.write( "so, we use zero product theorem to find the polynomial\r
\n" ); document.write( "\n" ); document.write( "given also \"f%28-1%29=-15\", but since all three roots are given, this will not be used\r
\n" ); document.write( "\n" ); document.write( "then \"+f%28x%29+=+%28x-x%5B1%5D%29+%28x-x%5B2%5D%29+%28x-x%5B3%5D%29\"\r
\n" ); document.write( "\n" ); document.write( " \"f%28x%29+=+%28x-2%29+%28x-2i%29+%28x-%28-2i%29%29\"\r
\n" ); document.write( "\n" ); document.write( " \"f%28x%29+=+%28x-2%29+%28x-2i%29+%28x%2B2i%29\"\r
\n" ); document.write( "\n" ); document.write( " \"f%28x%29+=+%28x-2%29+%28x%5E2-%282i%29%5E2%29\" \r
\n" ); document.write( "\n" ); document.write( " \"f%28x%29+=+%28x-2%29+%28x%5E2-4%28i%29%5E2%29\" \r
\n" ); document.write( "\n" ); document.write( " \"f%28x%29+=+%28x-2%29+%28x%5E2-4%28-1%29%29+\"\r
\n" ); document.write( "\n" ); document.write( " \"f%28x%29+=+%28x-2%29+%28x%5E2%2B4%29+\"\r
\n" ); document.write( "\n" ); document.write( "\"+f%28x%29+=+x%5E3%2B4x-2x%5E2-8\"\r
\n" ); document.write( "\n" ); document.write( " \"f%28x%29+=+x%5E3-2x%5E2%2B4x-8\"=> your answer\r
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\n" ); document.write( "\n" ); document.write( "now, we can check if \"f%28-1%29=-15\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28-1%29+=+%28-1%29%5E3-2%28-1%29%5E2%2B4%28-1%29-8\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28-1%29+=+-1-2%281%29-4-8\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28-1%29+=+-1-2-4-8\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28-1%29+=+-15\"\r
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