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Hard differentiation (1 Viewer)

Bdogz

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whats the derivitive wiht respect to x of ln(y-x) , i think u use implicit differentiation but i dont know how to do it
 

tommykins

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-1/ln(y-x)

you treat the y as a constant.
 

Bdogz

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Let dy/dx = y'

Therefore the derivative with respect to x of ln (y-x) would be:

oh k so wat wud be the derivative with respect to x of this equation : y=x^siny + x

i got 2 this step but im nto sure how much of it is right: dy/dx=(lnx.cosy.dy/dx + siny.1/x).e^sinylnx + 1
 
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tommykins

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is that y = x^siny + x or z= x^siny + x?

if the latter, dz/dx = x^sin(y)*sin(y)/x+1
 

Bdogz

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is that y = x^siny + x or z= x^siny + x?

if the latter, dz/dx = x^sin(y)*sin(y)/x+1
its a completely different question to the 1st thing i posted on here sorry, so the question is find dy/dx of y=x^siny + x
 

tommykins

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yeah i was curious as to why they had to do it.

not like its hard either lol
 

Drongoski

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Is it: y = xsin y + x ??

If so, is the answer ??




Edit: corrected: it's cos y not cos x; my typo.
 
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Bdogz

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Is it: y = xsin y + x ??

If so, is the answer ??


on the bottom line in denominator i got cosy instead of cosx, but apart from that i got wat u got, i dont hv the answer on me but once i get it ill notify u thanks

NB i shudve put this in the tertiary forum sorry
 
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-Onlooker-

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Functions of several vairables is not in the HSC, hence partial derivatives is beyond the scope of the syllabus.

You sure?

iirc; one of the hsc papers asked us to differentiate or integrate cos (x - y ). It was in the earlier years.

edit: It might not have asked us directly; might have been in the solutions, I can't remember 100% sorry.
 

Iruka

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There seems to be quite a bit of confusion of partial differentiation with implicit differentiation in this thread.

Implicit differentiation is in the syllabus; partial differentiation is not.
 

jchoi

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How does y = xsin y + x ?? turn into
?

Can someone show me the steps please? :)
 

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