document.write( "Question 1003892: Find a polynomial with real corfficients that has -2 and 2 + i as zeros \n" ); document.write( "
Algebra.Com's Answer #620507 by ankor@dixie-net.com(22740)\"\" \"About 
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Find a polynomial with real corfficients that has -2 and 2 + i as zeros
\n" ); document.write( "We have two factors from these zeros
\n" ); document.write( "x = -2
\n" ); document.write( "(x + 2) = 0
\n" ); document.write( "and
\n" ); document.write( "x = 2 + i
\n" ); document.write( "x - 2 = i
\n" ); document.write( "square both sides
\n" ); document.write( "(x-2)^2 = i^2
\n" ); document.write( "FOIL (x-2)(x-2); i^2 = -1
\n" ); document.write( "x^2 - 4x + 4 = -1
\n" ); document.write( "x^2 - 4x + 4 + 1 = 0
\n" ); document.write( "(x^2 - 4x + 5) = 0
\n" ); document.write( "Multiply these two factors
\n" ); document.write( "(x+2)(x^2 - 4x + 5) = x^3 - 2x^2 - 3x + 10 is polynomial
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "looks like this
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+14%2C+x%5E3+-+2x%5E2+-+3x+%2B+10%29+\" \n" ); document.write( "
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