Solving Limit of (1-cos(2x^2)) / (1-cos(3x^2)): Is There Another Way?

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SUMMARY

The limit of (1-cos(2x^2)) / (1-cos(3x^2)) as x approaches 0 results in an indeterminate form of 0/0. The discussion highlights the use of l'Hôpital's Rule, which initially leads to another 0/0 form. A more effective approach involves recognizing the limit property of sin(x)/x as x approaches 0, specifically that lim (x→0) sin(x)/x = 1. This insight allows for a more straightforward resolution of the limit without repeated application of l'Hôpital's Rule.

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Homework Statement


Find

limit ...(1-cos(2x^2)) / (1-cos(3x^2))
x->0

2. The attempt at a solution
since the above gave me 0/0, I used l'Hopital method..
then i got

(4x)sin(2x^2) / (6x)(sin3x^2)
which gives me 0/0 again..

so I kept on using l'Hopital.. but it seemed on going forever

is there other way to solve this..?
thank you in advance
 
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kira137 said:

Homework Statement


Find

limit ...(1-cos(2x^2)) / (1-cos(3x^2))
x->0

2. The attempt at a solution
since the above gave me 0/0, I used l'Hopital method..
then i got

(4x)sin(2x^2) / (6x)(sin3x^2)
which gives me 0/0 again..

so I kept on using l'Hopital..

Don't keep using LH rule. Remember you know (at least you should know):

\lim_{x\rightarrow 0}\frac {\sin x} x = 1

See if you can figure out how to use that next.
 
Using LH twice doesn't give 0/0.
 

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