Calxsolver
Precalculus

Exponential Equation Solver

An exponential equation has the unknown in the exponent. To solve a·bˣ = c, this tool isolates the power, then applies logarithms to bring the exponent down: x = ln(c/a) / ln(b).

Exponential Equation Solver

Solve a·bˣ = c for the exponent x.

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Frequently asked questions

Why do we use logarithms?

Logarithms are the inverse of exponentiation, so they move the unknown out of the exponent and into a solvable expression.

When is there no solution?

If c/a is zero or negative there is no real solution, because a positive base raised to any real power stays positive.

What values can the base take?

The base b must be positive and not equal to 1; b = 1 would make the left side constant.

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