How Do You Solve an Equation with Log for an Unknown Constant Plus Unknown?

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In summary, a logarithm is an operation represented by "log" that helps us solve exponential equations by isolating the variable in the exponent. This makes calculations easier and allows us to condense large numbers. To solve an equation with logarithms, we use properties such as the product, quotient, and power rules. These rules state that the logarithm of a product is the sum of the logarithms of the individual factors, the logarithm of a quotient is the difference of the logarithms of the individual terms, and the logarithm of a number raised to a power is the product of the power and the logarithm of the number. Logarithms can have negative values, but the base must be greater than 1 for the result
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likephysics
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Homework Statement


Can you solve an unknown equal to some constant+log of unknown.
please see attached.
All the other variables are known, except Ic1.
How to you solve this?

Homework Equations





The Attempt at a Solution


I have no idea.
 

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  • #2
If you have [itex]I_{C1}[/itex] both "inside" and "outside" the logarithm, the equation cannot be solved in terms of "elementary" functions. It very likely can be solved, though still non-trivial, in terms of the "Lambert W function" which is defined as the inverse function to [itex]f(x)= xe^x[/itex].
 

1. What is a logarithm?

A logarithm is an operation that helps us solve exponential equations. It is the inverse of the exponential function and is represented by the symbol "log".

2. Why do we use logarithms to solve equations?

Logarithms are useful in solving equations because they allow us to isolate the variable in the exponent and solve for it. They also help us condense large numbers and make calculations easier.

3. How do I solve an equation with logarithms?

To solve an equation with logarithms, you need to follow a few steps. First, use the properties of logarithms to simplify the equation. Then, isolate the variable by taking the logarithm of both sides. Finally, use algebraic techniques to solve for the variable.

4. What are the properties of logarithms?

The three main properties of logarithms are the product rule, quotient rule, and power rule. The product rule states that the logarithm of a product is equal to the sum of the logarithms of the individual factors. The quotient rule states that the logarithm of a quotient is equal to the difference of the logarithms of the individual terms. The power rule states that the logarithm of a number raised to a power is equal to the product of the power and the logarithm of the number.

5. Can logarithms have negative values?

Yes, logarithms can have negative values. However, the base of the logarithm must be greater than 1 in order for the result to be negative. If the base is between 0 and 1, the result will be a negative number raised to a power, which is not a real number. In general, logarithms can only be taken of positive numbers.

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