#Quick question about implicit derivatives

51 messages · Page 1 of 1 (latest)

limpid hollow
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I have searched and different sources tell me different results:
considering y(x) is the function ,is the implitcit derivative of sin(y) = 0 or y'cos(y)???
my logic tells me to do the power rule and do the internal derivative (y') * external derivative (cos)
wolframalpha and other math calculators tell me its 0.

pseudo oracleBOT
limpid hollow
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also just to double check while im here

y(x) ' = dx/dy or y(x)'= dy/dx?
I always get it confused and the research made me even more confused
Tho i think its the latter

minor copper
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Basically implicit differentiation relies on the chain rule

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For your first question, you need to say what sin(y) is equal to, if there’s no other functions you could just say sin(y) = a constant

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It’s the latter for your second question

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The derivative of sin(y) is cos(y) dy/dx

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Ie cos(y) y’

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But if sin(y) = a constant, then dy/dx = 0 (because 0 divided by cos(y) is 0)

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Assuming ofc that cos(y) isn’t 0

edgy pulsar
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,w d/dx sin(y(x))

edgy pulsar
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i wonder if your wolfram was differentiating sin(y) = 0, like bottle said eeveethink

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your thinking is right though

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to be pedantic, y(x)' isn't a notation, it's y'(x) = dy/dx

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if you need help remembering, you can pretend the apostrophe is a slash, then you get y/x which is like dy/dx catthumbsup

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just to remember which way around

limpid hollow
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thank you guys!

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whislt im here, im checking a completely different question about limits in which again
i have conflicinting answers
Would it be ok if i ask it here so i dont have to add another post ?

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or should i just make another post anyway

limpid hollow
edgy pulsar
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aha, you are taking the partial derivative of sin(y) with respect to x

limpid hollow
edgy pulsar
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this is a different thing to the derivative, which will come up in calc III, but basically you are asking wolfram to treat sin(y) as a constant

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kind of on them for calling this "implicit differentiation calculator"

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but just make sure it says $\dv{x}$ and not $\frac{\partial}{\partial{x}}$

limpid hollow
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yeah im not super used to using wolfram alpha so i dont really know honestly
I usually use other apps that are more common here

edgy pulsar
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fair, im not a big wolfram alpha person either

limpid hollow
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finished it all up

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but my girfrield just got into uni and she is taking calc 1

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so im revisiting everything again

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and as a good calc 1 student i remember almost nothing

tawny idolBOT
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haseeb

edgy pulsar
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sorry that was bothering me

limpid hollow
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np

edgy pulsar
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well, you know your partial derivatives then, so that's what happened :P

edgy pulsar
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i think for your limits question you should make another post

limpid hollow
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okay

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fair

edgy pulsar
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yeah theres no hard rule but seems different enough of a q for me

limpid hollow
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its quite ironic that calc 4 was actually the easiet

edgy pulsar
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lol that's definitely different to my experience 😅 i think i remembered the most out of calc 3

limpid hollow
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calc 3 was my favorite but
calc 4 was easier

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i liked sums and series and such

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dont actually remember much from calc 4 but i got a 9.2 or smth in my final grade
just remember it being chill

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hopefully i havent forgotten it qwbjhenqweqw

verbal stump
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https://tutorial.math.lamar.edu/
a useful website i found

limpid hollow
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how do i change the tags to solved again