document.write( "Question 707551: x^4-8x^2+16=0 \n" ); document.write( "

Algebra.Com's Answer #435735 by nerdybill(7384) $\"\"$ $\"About$

You can put this solution on YOUR website!
x^4-8x^2+16=0
\n" ); document.write( "we can factor the above as:
\n" ); document.write( "(x^2-4)(x^2-4) = 0
\n" ); document.write( "(x^2-4)^2 = 0
\n" ); document.write( ".
\n" ); document.write( "But:
\n" ); document.write( "(x^2-4)
\n" ); document.write( "can be rewritten as
\n" ); document.write( "(x^2-2^2) \"difference of squares\" (special case)
\n" ); document.write( "can itself be factored as:
\n" ); document.write( "(x-2)(x+2)
\n" ); document.write( ".
\n" ); document.write( "That means:
\n" ); document.write( "(x^2-4)^2 = 0
\n" ); document.write( "is the same as:
\n" ); document.write( "[(x-2)(x+2)]^2 = 0
\n" ); document.write( "(x-2)(x+2)(x-2)(x+2) = 0
\n" ); document.write( "(x-2)^2(x+2)^2 = 0 (this is the factored form)
\n" ); document.write( ".
\n" ); document.write( "Solution:
\n" ); document.write( "x = {-2,2}
\n" ); document.write( " \n" ); document.write( "

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