document.write( "Question 731799: Find a polynomial f(x) of degree 3 that has the indicated zeros and satisfies the given condition.
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document.write( "-2i, 2i, 5; f(1) = 80\r
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document.write( "I tried this:\r
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document.write( "(x+2i)(x-2i)(x-5) = x^3-5x^2+4x-20\r
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document.write( "Then I solved this:\r
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document.write( "80=a(1+2i)(1-2i)(1-5)
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document.write( "80=a(20)
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document.write( "a=4\r
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document.write( "Then I combined the two, and I got:\r
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document.write( "4(x^3-5x^2+16x-80)
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document.write( "=4x^3-20x^2+16x-80\r
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document.write( "This is wrong. Any ideas where I went wrong? \n" );
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Algebra.Com's Answer #447291 by vabryant09(1)![]() ![]() ![]() You can put this solution on YOUR website! I figured it out, I had the wrong sign. \n" ); document.write( " |