document.write( "Question 188390: Find the zeroes of f(x) = x^4-x^3-4x^2+4x.\r
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Algebra.Com's Answer #141231 by stanbon(75887)\"\" \"About 
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Find the zeroes of f(x) = x^4-x^3-4x^2+4x
\n" ); document.write( "x^4-x^3-4x^2+4x = 0
\n" ); document.write( "Factor:
\n" ); document.write( "x(x^3-x^2-4x+4) = 0
\n" ); document.write( "x = 0 is one of the zeroes.
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\n" ); document.write( "Since the coefficients of x^3-x^2-4x+4 add up zero, x=1 is a zero.
\n" ); document.write( "Use synthetic division to find the other zeroes:
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\n" ); document.write( "1)....1....-1....-4....4
\n" ); document.write( ".......1.....0.....-4..|..0\r
\n" ); document.write( "\n" ); document.write( "The remaining factor is x^2-4 which
\n" ); document.write( "factors as (x-2)(x+2).
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\n" ); document.write( "So, the four zeroes are x= 0 or x=1 or x = 2 or x=-2
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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