How do you solve e^x-9=19ex9=19?

1 Answer
Aug 30, 2017

Real solution:

x = ln 28x=ln28

Complex solutions:

x = ln 28 + 2npii" "n in ZZ

Explanation:

Given:

e^x-9 = 19

Add 9 to both sides to get:

e^x = 28

Take the natural log of both sides to get:

x = ln(28)

More generally note that:

e^(x+2npii) = e^x*e^(2npii) = e^x" " for any integer n

So if we include complex solutions, we have:

x = ln 28+2npii" "n in ZZ