SOLUTION: Evaluate limit as x approaches 0 of (cos3x-cos4x)/x^2 I have tried using L'Hopital's but differentiating the function using the quotient rule keeps squaring the denominator.

Algebra ->  Trigonometry-basics -> SOLUTION: Evaluate limit as x approaches 0 of (cos3x-cos4x)/x^2 I have tried using L'Hopital's but differentiating the function using the quotient rule keeps squaring the denominator.      Log On


   

Question 591060: Evaluate limit as x approaches 0 of (cos3x-cos4x)/x^2
I have tried using L'Hopital's but differentiating the function using the quotient rule keeps squaring the denominator.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
When you use L'Hopital's rule, you differentiate the numerator and denominator SEPARATELY.

Let me know what you get when you do this.