Calculus 1 Solving logarithmic equation

destinc
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Solve for b,
f(x)=b^x

Here is where I am so far
lny=lnb^x
lny=xlnb^x
y'/y= lnb
e^y'/y= e^lnb
b= e^y'/y

My question is, can I simplify the exponent y'/y any further, or is my answer good here?
Thank you
 
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You say to solve for b in the function f\left(x\right) = b^{x}. From the answer provided you solve for b in terms of f\left(x\right) and f'\left(x\right). Does the original problem ask for you to solve for b in terms of these functions? It is possible to solve for b in terms of only x and f\left(x\right).
 
It does not require taking the derivative, that was simply the first idea I had. If there is an alternate way, please show me
 
Look at the second line of the work that you have already provided. It should actually be ln\left(y\right) = xln\left(b\right). If x is not equal to zero, then you can divide both sides by x. The rest of the simplification is left to you.
 
destinc said:
Solve for b,
f(x)=b^x

Here is where I am so far
lny=lnb^x
lny=xlnb^x This line should be lny=xlnb. It shouldn't have bx.
y'/y= lnb
e^y'/y= e^lnb
b= e^y'/y

My question is, can I simplify the exponent y'/y any further, or is my answer good here?
Thank you
Rather than using logs, take both sides of the equation, y=bx, to the 1/x power.
 
thanks, I made the problem so much harder than I needed to. The redirect helped.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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