I have been happilly solving away a multitude of different questions until the book threw me this curve ball...10^(3x)(adsbygoogle = window.adsbygoogle || []).push({});

My first attempt was as follows: let y=u^3 and u=10^x

dy/du = 3u^2...du/d10 = x(10^(x-1))...3x(10^2x(10^(x-1)))...3x(10^(3x-1))

the answer given in the book however is (3ln10)10^3x...thing is I haven't met a question of this type (they have been of the sort..((x^3)^1/2)/ln(x-2) etc...) and so my best attempt to reach this answer so far is to say that 10^3X is equivilant to saying e^3xln10.

If y = e^u and u = 3xln10 then...

dy/du = e^u and du/dx = 3ln10 + (3x/10) giving...(3ln10+(3x/10))10^3xproblem is...I have not reached the answer and I am not sure how I've gone wrong...please help!

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# Homework Help: Differentiating compound functions

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