Differentiate Exponential Functions

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rocomath
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this is an even problem of my homework so there is no answer

i think i did it right, i would just like a thumbs up/down ... thanks

[tex]y=2^{3^{x^{2}}}}[/tex]

[tex]\ln{y}=\ln2^{3^{x^{2}}}}[/tex]

[tex]\ln{y}=3^{x^{2}}}\times\ln2[/tex]

[tex]\frac{y'}{2^{3^{x^{2}}}}}=\ln2\times3^{x^{2}}}\times\ln3\times2x[/tex]

[tex]y'=2x\times2^{3^{x^{2}}}}\times3^{x^{2}}}\ln2\times\ln3[/tex]
 
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thumbs up

but a faster method is to do the chain rule and remember that:

[tex] y=a^x[/tex]
[tex]y'=a^xlna[/tex]
 
bob1182006 said:
thumbs up

but a faster method is to do the chain rule and remember that:

[tex] y=a^x[/tex]
[tex]y'=a^xlna[/tex]

hmm... that's not actually too useful here, is it?

Perhaps more useful is something along the lines of:

If
[tex] y(x)=a^{f(x)}[/tex]

then
[tex] y'(x)=a^{f(x)}\ln(a)f'(x)[/tex]
 
olgranpappy said:
hmm... that's not actually too useful here, is it?

Perhaps more useful is something along the lines of:

If
[tex] y(x)=a^{f(x)}[/tex]

then
[tex] y'(x)=a^{f(x)}\ln(a)f'(x)[/tex]
i like that
 
olgranpappy said:
hmm... that's not actually too useful here, is it?

Perhaps more useful is something along the lines of:

If
[tex] y(x)=a^{f(x)}[/tex]

then
[tex] y'(x)=a^{f(x)}\ln(a)f'(x)[/tex]
Of course, you are doing exactly what bob said to do.
 
so i was looking over my homework and found a few mistakes on some of them (even problems)

i'm suppose to simplify this problem.

1st one

[tex]e^{x+\ln{x}}[/tex]

[tex]e^{x}\times e^{\ln{x}}[/tex]

[tex]xe^{x}[/tex] should this be my final answer?

[tex]e^{x^{2}}[/tex] can i do this step or can i not assume it is was a power of?
 
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Hurkyl said:
Of course, you are doing exactly what bob said to do.

No. His suggestion was a special case of mine having f(x)=x.

...
...
 
rocophysics said:
so i was looking over my homework and found a few mistakes on some of them (even problems)

i'm suppose to simplify this problem.

1st one

[tex]e^{x+\ln{x}}[/tex]

[tex]e^{x}\times e^{\ln{x}}[/tex]

[tex]xe^{x}[/tex]

Stop there! The next line does not follow

bad! said:
[tex]e^{x^{2}}[/tex]

Nooooo. that is not a property of the exponential. You are confusing the properties of exponentials and logs...
 
olgranpappy said:
No. His suggestion was a special case of mine having f(x)=x.
He said to use the chain rule. What you wrote is what you get when you combine the chain rule with (a^x)' = a^x ln a
 
Hurkyl said:
He said to use the chain rule. What you wrote is what you get when you combine the chain rule with (a^x)' = a^x ln a

So what? You said "exactly", but it was not "exactly what bob said to do".

I'm just pointing that out. Don't you agree?