Valkiyare
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#1
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#1
Hello everyone,

I have no idea how to start solving these questions I’ve been set. Could someone please explain to me what to do to arrive at an answer? I have shared the link to the picture of the questions(from Question 19)

http://imgur.com/ZRKHXVq

Thank you!
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the bear
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f'(2) means dy/dx when x is 2

if y = g(x) + 8x -1 for instance,

then dy/dx = g'(x) + 8
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Valkiyare
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#3
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(Original post by the bear)
f'(2) means dy/dx when x is 2

if y = g(x) + 8x -1 for instance,

then dy/dx = g'(x) + 8
Thank you - I think I’m still a bit confused 😅 sorry
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SerBronn
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You need to revise the chain rule:

{d \over dx}(f(g(x)) = {df \over dg} \times {dg \over dx}

So, for example, if f(x) = sin(g(x)) then {df \over dx} = cos(g(x)) \times {dg \over dx}
Last edited by SerBronn; 2 years ago
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the bear
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(Original post by SerBronn)
You need to revise the chain rule:

{d \over dx}(f(g(x)) = {df \over dg} \times {dg \over dx}

So, for example, if f(x) = sin(g(x)) then {df \over dx} = cos(g(x)) \times {dg \over dx}
that is a very confusing way to "help" someone who is struggling with the chain rule.
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SerBronn
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(Original post by the bear)
that is a very confusing way to "help" someone who is struggling with the chain rule.
Giving him the formula to use and a worked example is 'very confusing'? :confused::confused::confused:
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the bear
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(Original post by SerBronn)
Giving him the formula to use and a worked example is 'very confusing'? :confused::confused::confused:
the formula is not easy to understand for someone who is having difficulties.
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