How to Find the Limit of sin(3x²)/(8x) as x Approaches Zero?

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Dan350
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1.
what would be the limit?? without using the L'Hopital's rule

lim_(x-0) (sin(3 x^2))/(8 x)


the limit of sin(3x^2) divided by 8x as x approaches zero











2. Limits of trignometric functions



3. The Attempt at a Solution
I tried factoring out the 1/8, but that's it, Idk how to go on


Hope you can help me

Thanks


 
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Dan350 said:
1.
what would be the limit?? without using the L'Hopital's rule

lim_(x-0) (sin(3 x^2))/(8 x)the limit of sin(3x^2) divided by 8x as x approaches zero


2. Limits of trignometric functions
3. The Attempt at a Solution
I tried factoring out the 1/8, but that's it, Idk how to go onHope you can help me

Thanks

What's lim x->0 of sin(3x^2)/(3x^2)? That should be a good hint.
 
Last edited:
Dick said:
What's lim x->0 of sin(3x^2)/(3x^2)? That should be a good hint.



1


but how to put the 3x^2 below?
 
Dan350 said:
1but how to put the 3x^2 below?

What (expression) do you have to multiply 8x by to get 3x2? As long as you multiply both the top and bottom by the same, you don't change the fraction.
 
Curious3141 said:
What (expression) do you have to multiply 8x by to get 3x2? As long as you multiply both the top and bottom by the same, you don't change the fraction.

3x on both numerator and denominator?
i would get 24x^2, but i can split the fraction right?
 
Dan350 said:
3x on both numerator and denominator?
i would get 24x^2, but i can split the fraction right?

So you get ##\frac{3x\sin(3x^2)}{8(3x^2)}##. What happens next?
 
Curious3141 said:
So you get ##\frac{3x\sin(3x^2)}{8(3x^2)}##. What happens next?



We factor out.

then the limx-0 of 3x/8 and limx-0 of sin(3x^2)/3x^2
therefore

limx-0 0*1
so

limx-0f(x)= 0
 
Dan350 said:
We factor out.

then the limx-0 of 3x/8 and limx-0 of sin(3x^2)/3x^2
therefore

limx-0 0*1
so

limx-0f(x)= 0

Yes, exactly.
 
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