Limit of (sin(2x))^3/(sin(3x))^3 as x Approaches 0: Solution

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SUMMARY

The limit of (sin(2x))^3/(sin(3x))^3 as x approaches 0 evaluates to 8/27. This result is derived from the known limit of sin(x)/x as x approaches 0, which equals 1. By applying this concept, one can manipulate the expression by multiplying and dividing by appropriate powers of x to simplify the limit calculation without using L'Hôpital's rule.

PREREQUISITES
  • Understanding of limits in calculus
  • Familiarity with the limit of sin(x)/x as x approaches 0
  • Basic algebraic manipulation skills
  • Knowledge of trigonometric functions
NEXT STEPS
  • Review the limit properties of trigonometric functions
  • Practice evaluating limits involving sin(x) and cos(x)
  • Learn techniques for simplifying complex limits without L'Hôpital's rule
  • Explore the Taylor series expansion for sin(x) near x = 0
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Students studying calculus, particularly those focusing on limits and trigonometric functions, as well as educators looking for effective methods to teach limit evaluation techniques.

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Homework Statement


evaluate the limit as x approaches 0 of (sin(2x))^3/(sin(3x))^3


Homework Equations





The Attempt at a Solution


the answer in the textbook is 8/27
i figured they got that by raising 2 to the 3rd and 3 to the 3rd
but I'm not entirely sure what happens to the sin's

id really appreciate a worked out answer (that doesn't use l'hopital's rule)
 
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Nitrate said:

Homework Statement


evaluate the limit as x approaches 0 of (sin(2x))^3/(sin(3x))^3


Homework Equations





The Attempt at a Solution


the answer in the textbook is 8/27
i figured they got that by raising 2 to the 3rd and 3 to the 3rd
but I'm not entirely sure what happens to the sin's

id really appreciate a worked out answer (that doesn't use l'hopital's rule)

We don't do worked out answers. But here's a hint: Presumably you know something about the limit of sin(x)/x as x → 0. Make use of that by multiplying and dividing by certain powers of x.
 
LCKurtz said:
We don't do worked out answers. But here's a hint: Presumably you know something about the limit of sin(x)/x as x → 0. Make use of that by multiplying and dividing by certain powers of x.

well
lim
x->0 sinx/x = 1
the problem is that i don't know how to apply it to this question
 
Nitrate said:
well
lim
x->0 sinx/x = 1
the problem is that i don't know how to apply it to this question

What would be the limit of \frac {\sin(2x)}{2x} as x → 0?
 
LCKurtz said:
What would be the limit of \frac {\sin(2x)}{2x} as x → 0?
that limit would be 1 as well
but I'm still not sure how it'd help
 
Nitrate said:
that limit would be 1 as well
but I'm still not sure how it'd help

Now read the hint I gave in post #2 again. Hopefully you will see it; I'm signing off for tonight.
 

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