document.write( "Question 920810: I have two problems with factorization. I tried everything, in many ways, but can't find the right answer.\r
\n" ); document.write( "\n" ); document.write( "First:
\n" ); document.write( "\"%28x-1%29%5E3+%2B+8\"\r
\n" ); document.write( "\n" ); document.write( "The answer is:
\n" ); document.write( "\"%28x%2B1%29%28x%5E2-4x%2B7%29\"\r
\n" ); document.write( "\n" ); document.write( "Second:
\n" ); document.write( "\"x%5E4%2Bx%5E2y%5E2%2By%5E4\"\r
\n" ); document.write( "\n" ); document.write( "Answer:
\n" ); document.write( "\"%28x%5E2%2Bxy%2By%5E2%29%28x%5E2-xy%2By%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "Thank you!
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Algebra.Com's Answer #558586 by rothauserc(4718)\"\" \"About 
You can put this solution on YOUR website!
1) We can factor the sum of cubes using the following formula:
\n" ); document.write( "x^3 + y^3 = (x+y)(x^2-xy+y^2)
\n" ); document.write( "we are given (x-1)^3 + 2^3
\n" ); document.write( "therefore we get
\n" ); document.write( "(x-1+2)((x-1)^2 -(x-1)2 +4))
\n" ); document.write( "(x+1)(x^2-2x+1 -2x +2 +4)
\n" ); document.write( "(x+1)(x^2 -4x +7)
\n" ); document.write( "2) Let a = x^2
\n" ); document.write( "Let b = y^2.
\n" ); document.write( "So lets substitute the values of a and b in for x^2 and y^2:
\n" ); document.write( "a^2 + ab + y^2
\n" ); document.write( "If you know that (a + b)^2 = a^2 + 2ab + b^2, then you can see that the two expressions are similar.
\n" ); document.write( "lets just add one set of \"ab\" to the first equation, so that we get a^2 + 2ab + b^2, which is easily simplified.
\n" ); document.write( "therefore, we would get:
\n" ); document.write( "(a + b)^2 - ab <----if we added ab, we must now subtract it.
\n" ); document.write( "now, just substitute the values of a and b back in:
\n" ); document.write( "(x^2 + y^2)^2 - x^2y^2 then apply the difference of squares here.
\n" ); document.write( "(x^2 + y^2) - (xy)^2
\n" ); document.write( "(x ^2 + y^2 + xy) (x^2 + y^2 - xy)
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