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mathcalculus
 one year ago
hello guys, can someone help me with related rates?
(attached)
mathcalculus
 one year ago
hello guys, can someone help me with related rates? (attached)

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Psymon
 one year ago
Best ResponseYou've already chosen the best response.0Eww, word problems *waits for the problem and prepares sword*

Psymon
 one year ago
Best ResponseYou've already chosen the best response.0Oh, not a word problem :D okay, np with this one

Psymon
 one year ago
Best ResponseYou've already chosen the best response.0So whenever you take the derivative of y, you can mark it with (dy/dx). Whenever you take the derivative of an x, you can mark it with (d/dx). So take the derivative of both sides, put dy/dx and d/dx where necessary, and plug in the given values.

zzr0ck3r
 one year ago
Best ResponseYou've already chosen the best response.1the derivative of 7x^3  10x with respect to t Is 0

pgpilot326
 one year ago
Best ResponseYou've already chosen the best response.1dx/dt = 0 so will dy/dt

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0alright let me try this step by step.

zzr0ck3r
 one year ago
Best ResponseYou've already chosen the best response.1y is in terms of x, there are no t's so treat x's like a constant derivative of a constant is 0

Psymon
 one year ago
Best ResponseYou've already chosen the best response.0Pretty much. They made it a little easy on ya with there being a dx/dt, haha. But itd be nice practice if we said it was d/dx and made d/dx equal to 1.

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0okay so the derivative to this would be: 21x^210

zzr0ck3r
 one year ago
Best ResponseYou've already chosen the best response.1with respect to x, yes but they ask for it with respect to t (not x)

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0okay. so do i multiply each by dx/dt?

Psymon
 one year ago
Best ResponseYou've already chosen the best response.0Its like theyre saying, there is no t for there to be a derivative in respect to, so everything is 0. Thats why I said we should change the conditions of the problem for practice.

zzr0ck3r
 one year ago
Best ResponseYou've already chosen the best response.1\[\frac{d(f(x))}{dt}=0\]

pgpilot326
 one year ago
Best ResponseYou've already chosen the best response.1x is some function of t, thus when we take the derivative of y with respect to t, we get \[\frac{ dy }{ dt }=\frac{ d }{ dt }\left( 7x ^{3}10x \right)=\frac{ d }{ dt }\left( 7x ^{3} \right)\frac{ d }{ dt }\left( 10x \right)=21x ^{2}\frac{ dx }{ dt }10\frac{ dx }{ dt }\]form there it's plug in what you know and compute

pgpilot326
 one year ago
Best ResponseYou've already chosen the best response.1since dx/dt is 0, dy/dt is 0. y only depends on x. look at te function. if x doesn't change, neither will y. the math proves it.

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0question: why would it be zero?

pgpilot326
 one year ago
Best ResponseYou've already chosen the best response.1the problem states that dx/dt = 0

pgpilot326
 one year ago
Best ResponseYou've already chosen the best response.1each term in dy/dt is multiplied by dx/dt

pgpilot326
 one year ago
Best ResponseYou've already chosen the best response.1no, d/dt is an operator. it says take the derivative of wht follows with respect to t.

pgpilot326
 one year ago
Best ResponseYou've already chosen the best response.1dy/dt is the derivative of y with respect to t.

pgpilot326
 one year ago
Best ResponseYou've already chosen the best response.1do you know the chain rule for derivatives?

mathcalculus
 one year ago
Best ResponseYou've already chosen the best response.0sort of, I need to refresh my memory with the chain rule.
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