document.write( "Question 103071: I am totally stumped at the end and need some help.
\n" ); document.write( " 16x^4 - 40x^2 + 9
\n" ); document.write( "I have: (4x^2 -1) (4x^2 -9) and now I'm lost. Can someone help me to factor this completely where I can understand. Thank you. \n" ); document.write( "

Algebra.Com's Answer #74935 by Earlsdon(6294) $\"\"$ $\"About$

You can put this solution on YOUR website!
You are obviously not \"totally\" stumped as your first step is definitely good.
\n" ); document.write( "Factor:
\n" ); document.write( " $\"16x%5E4-40x%5E2%2B9+=+%284x%5E2-1%29%284x%5E2-9%29\"$ Notice that these two factors are the difference of squares. The difference of squares can be factored thus:
\n" ); document.write( " $\"A%5E2-B%5E2+=+%28A-B%29%28A%2BB%29\"$ So, applying this to your result, we get:
\n" ); document.write( " $\"%284x%5E2-1%29%284x%5E2-9%29+=+%282x-1%29%282x%2B1%29%282x-3%29%282x%2B3%29\"$ \n" ); document.write( "

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