Calculus 1 Solving logarithmic equation

In summary, the conversation discussed solving for b in the function f(x)=b^x and the use of logs and exponents to simplify the problem. It was suggested to take both sides of the equation, y=bx, to the 1/x power as a simpler approach.
  • #1
destinc
17
0
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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  • #2
You say to solve for b in the function [itex]f\left(x\right) = b^{x}[/itex]. From the answer provided you solve for b in terms of [itex]f\left(x\right)[/itex] and [itex]f'\left(x\right)[/itex]. 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 [itex]x[/itex] and [itex]f\left(x\right)[/itex].
 
  • #3
It does not require taking the derivative, that was simply the first idea I had. If there is an alternate way, please show me
 
  • #4
Look at the second line of the work that you have already provided. It should actually be [itex]ln\left(y\right) = xln\left(b\right)[/itex]. If x is not equal to zero, then you can divide both sides by x. The rest of the simplification is left to you.
 
  • #5
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.
 
  • #6
thanks, I made the problem so much harder than I needed to. The redirect helped.
 

FAQ: Calculus 1 Solving logarithmic equation

1. What is a logarithmic equation?

A logarithmic equation is an equation where the variable appears in the exponent of a logarithm.

2. How do you solve a logarithmic equation?

To solve a logarithmic equation, you must isolate the logarithm on one side of the equation and then apply the inverse of the logarithmic function, which is the exponential function, to both sides.

3. What is the difference between natural logarithms and common logarithms?

Natural logarithms use a base of e, which is approximately 2.718, while common logarithms use a base of 10. Natural logarithms are typically denoted as ln(x), while common logarithms are denoted as log(x).

4. Can I use a calculator to solve logarithmic equations?

Yes, you can use a calculator to solve logarithmic equations. However, it is important to understand the steps involved in solving the equation by hand in order to use the calculator correctly.

5. How is calculus used to solve logarithmic equations?

Calculus is used to solve logarithmic equations by taking the derivative of both sides of the equation and then using algebraic manipulation to isolate the variable. This process is known as logarithmic differentiation.

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