document.write( "Question 591060: Evaluate limit as x approaches 0 of (cos3x-cos4x)/x^2
\n" ); document.write( "I have tried using L'Hopital's but differentiating the function using the quotient rule keeps squaring the denominator. \n" ); document.write( "

Algebra.Com's Answer #375473 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
When you use L'Hopital's rule, you differentiate the numerator and denominator SEPARATELY.\r
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\n" ); document.write( "\n" ); document.write( "Let me know what you get when you do this. \n" ); document.write( "

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