Alright, the question is:

transform

into by using the substitution

I'm stuck on differentiatin twice (Worried)

Help, please?

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- Jun 14th 2008, 10:14 AMSilverDifferentiating twice
Alright, the question is:

transform

into by using the substitution

I'm stuck on differentiatin twice (Worried)

Help, please? - Jun 14th 2008, 10:53 AMSilver
Pretty please?

No?? (Worried)

- Jun 14th 2008, 11:35 AMTwistedOne151Question
In the result you're trying to get, are the derivatives of y supposed to be with respect to t, or with respect to x (as you have it written)? I'm pretty sure it should be the former.

--Kevin C. - Jun 14th 2008, 12:40 PMSilver
- Jun 14th 2008, 01:25 PMTwistedOne151Chain rule
Apply the chain rule. You should have gotten from that

,

as you said it was the second derivative you had trouble with.

The key is to differentiale both sides of the above result with respect to t:

.

Use the product rule:

.

Now apply the chain rule to the remaining derivative:

And you should be able to proceed from here.

--Kevin C. - Jun 14th 2008, 01:56 PMSoroban
Hello, Silver!

Is there a typo? . . . Is there really a**square**in the equation?

. . Without the square, I can do it*(backwards).*

Quote:

Transform .

by using the substitution

We have: .

Then: .

Substitute into: .

. . . .

. .

Multiply by

- Jun 14th 2008, 01:59 PMSilver
there is definitely a square, but thanks anyway :)