document.write( "Question 1085361: f(x)=28x^4-8x^3-36x^2+112x-144
\n" ); document.write( "need to factor that completely. Then after that need to find all the zeros of the function. \n" ); document.write( "
Algebra.Com's Answer #699420 by Boreal(15235)\"\" \"About 
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28x^4-8x^3-36x^2+112x-144=
\n" ); document.write( "4(7x^4-2x^3-9x^2+28x-36)
\n" ); document.write( "synthetic division with -2\r
\n" ); document.write( "\n" ); document.write( "-2/7==-2==-9==28==-36
\n" ); document.write( "==7==-16--23---18===0
\n" ); document.write( "(x+2) is a factor (7x^3-16x^2+23x-18))
\n" ); document.write( "graphing this shows 9/7 as a root.
\n" ); document.write( "Therefore (7x-9) is a factor.
\n" ); document.write( "Multiply (x+2)(7x-9) to get 7x^2+5x-18
\n" ); document.write( "Divide that into the 7x^4-2x^3-9x^2+28x-36 and the result is x^2-x+2, which has complex roots.
\n" ); document.write( "roots are -2 and 9/7
\n" ); document.write( "factors are 4(x+2)(x^2-x+2)(7x-9)\r
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\n" ); document.write( "\n" ); document.write( "\"graph%28300%2C300%2C-5%2C10%2C-100%2C10%2C7x%5E4-2x%5E3-9x%5E2%2B28x-36%29\"
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