document.write( "Question 418197: I am working on expressing negative square roots in terms of j. For example: I have 4* the square root of -8 when i put it in the calculator it comes up 11.313j but the back of the book says 8j* square root of 2. If i put that into the calculator i get the same answer as i was getting before. 11.313j. I don't know how to get the answer in the back of the book. \n" ); document.write( "
Algebra.Com's Answer #292735 by nerdybill(7384)\"\" \"About 
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For example: I have 4* the square root of -8 when i put it in the calculator it comes up 11.313j but the back of the book says 8j* square root of 2. If i put that into the calculator i get the same answer as i was getting before. 11.313j. I don't know how to get the answer in the back of the book.
\n" ); document.write( ".
\n" ); document.write( "The answer in the back of your book is the \"exact\" answer.
\n" ); document.write( "Whereas, the answer you calculated is the approximate \"decimal\" equivalent.
\n" ); document.write( ".
\n" ); document.write( "realize that:
\n" ); document.write( "\"sqrt%28-1%29+=+j\"
\n" ); document.write( ".
\n" ); document.write( "Thus, your problem:
\n" ); document.write( "\"4%2Asqrt%28-8%29\"
\n" ); document.write( "can be factored as:
\n" ); document.write( "\"4%2Asqrt%28%28-1%29%282%29%282%29%282%29%29\"
\n" ); document.write( "we can extract the -1 under the radical and get:
\n" ); document.write( "\"4j%2Asqrt%28%282%29%282%29%282%29%29\"
\n" ); document.write( "finally, we can pull out a \"pair\" of the 2's to get:
\n" ); document.write( "\"4%282%29j%2Asqrt%282%29\"
\n" ); document.write( "\"8j%2Asqrt%282%29\"
\n" ); document.write( " \n" ); document.write( "
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