The derivative of 4^x + 3^x + 9^-x would be zero.

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EvilPony
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if anyone can teach me how to do this that would be great, thanks.

dereiv. means derivative sorry
 
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EvilPony said:
if anyone can teach me how to do this that would be great, thanks.

dereiv. means derivative sorry

when I am doing something with the form something raised to x i always remember - keep the tern , log (or ln, same meaning here) the base number

and then differentiate the exponent

for example for [tex]\frac{d}{dx} (3^x) = 3^x Log3 (1)[/tex]

as you can see keep the function 3^x, log the base Log3, and then differentiate the numerator (1).
 
All I can say to the above post, is eh? That would mean that it would be 0. In general:

[tex]\frac{d}{dx} \left( a^x \right) = \ln (a) \; a^x[/tex]

Where a is some constant. Here is the method used to work it out and generally useful for this type of problem:

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

[tex]\ln y = \ln \left( a^x \right)[/tex]

[tex]\ln y = x \ln a[/tex]

[tex]\frac{dy}{dx} \frac{1}{y} = \ln a[/tex]

[tex]\frac{dy}{dx} = (\ln a)y[/tex]

[tex]\frac{d}{dx} \left( a^x \right) = \ln (a) \; a^x[/tex]
 
Zurtex said:
All I can say to the above post, is eh? That would mean that it would be 0. In general:

[tex]\frac{d}{dx} \left( a^x \right) = \ln (a) \; a^x[/tex]

Where a is some constant. Here is the method used to work it out and generally useful for this type of problem:

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

[tex]\ln y = \ln \left( a^x \right)[/tex]

[tex]\ln y = x \ln a[/tex]

[tex]\frac{dy}{dx} \frac{1}{y} = \ln a[/tex]

[tex]\frac{dy}{dx} = (\ln a)y[/tex]

[tex]\frac{d}{dx} \left( a^x \right) = \ln (a) \; a^x[/tex]
what would be zero??