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#1 2006-01-08 04:41:45

george
Guest

Diffrentiation

Hello all, hope everybody has had a happy new year..

I have a little trouble with this differential question

y=3x^6 + sin2x +e^2x + e^4x log e^2x

i need to find dy/dx.

I would be grateful for an answer


Thanks

#2 2006-01-08 05:25:02

God
Member
Registered: 2005-08-25
Posts: 59

Re: Diffrentiation

y=3x^6 + sin2x +e^2x + e^4x log e^2x

Use power rule for 3x^6 -> 18x^5
Use chain rule for next two terms:
e^2x -> 2e^2x; sin2x -> 2cos2x

so so far that's dy/dx = 18 x^5 + 2 cos2x + 2 e^2x + ...

... can you put parenthases in the last term so that I know what exactly it says?

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#3 2006-01-08 05:28:28

george
Guest

Re: Diffrentiation

I knew god would help me....lol

Thanx


If y = 3x^6 + sin2x + e^2x + e^4x log e^2x

Find dy/dx

??

#4 2006-01-08 05:30:07

God
Member
Registered: 2005-08-25
Posts: 59

Re: Diffrentiation

is log natural log or base 10?

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#5 2006-01-08 05:33:14

george
Guest

Re: Diffrentiation

it is natural log

#6 2006-01-08 06:06:55

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: Diffrentiation

I'm going to jump in here and assume that it means e^4x * ln (e^2x).

The e and the ln cancel each other out, so you're left with 2x*e^4x.

And to differentiate that, you use the product rule: (uv)' = uv' + vu'.

d(2x*e^4x)/dx = 8x*e^4x + 2*e^4x = e^4x(8x+2)

Put that together with what God already found, and you get: dy/dx = 18 x^5 + 2 cos2x + 2 e^2x + e^4x(8x+2)


Why did the vector cross the road?
It wanted to be normal.

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