Check out this Calculus Question and Its Correct Answer - Expert Reviewed!"

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The discussion revolves around a calculus question and its answer, with participants reviewing the correctness of the notation used. One commenter points out inconsistencies in the notation, particularly regarding the use of "dy/dx" versus "d/dt" in derivatives. Another participant highlights that the notation should reflect standard mathematical practices, emphasizing that "dy/dt" implies the derivative of the original function rather than a single term. The conversation concludes with a consensus that the last line of the solution should correctly state "dy/dt = ..." instead of "dy/dx = ...". Overall, the thread focuses on clarifying proper calculus notation and ensuring accuracy in derivative expressions.
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hi,

Below i have attched both my question and answer. Can someone please take a look and tell me if its right? Thanks in advance!
 

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anyone please and thank you!
 
Looks absolutely fine to me. Good work.

A bit weird that there is a t on the top and bottom at the start though.

Interesting method of notation too. I always used write in extra u's and v's for the quotient differential, etc. but you've kept it in y's and t's
 
His notation is wrong (or at least, not consistent with any sort of standard mathematical notation).

y = f(x) \Longrightarrow \frac{dy}{dx} = \frac{d}{dx} f(x) \neq \frac{dy}{dx}f(x),

(unless f(x), and hence y, is constant)
 
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so how is it suppose to be? i don't get you
 
On line 2, on the right hand side where you have the fraction dy/dt, tehre should not be a y. It should be

\frac{d}{dt} (\frac{t-6}{t+6})
 
You did it more than once,

dy/dt implies the derivative of th eoriginal function, which isn't what your doing in every step, you are taking a derivative of a single term inthe function, hence (d/dt) not (dy/dt)
 
Look at my last post, then look at your work.

\frac{dy}{dx}f(x)

means that you are multiplying the derivative of y by f(x). On the other hand,

\frac{d}{dx}f(x)[/itex]<br /> <br /> means that you are taking the derivative <i>of</i> f(x).
 
thanks guys..got you
 
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Also the last line should read "dy/dt = ..." and not "dy/dx = ...".
 
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