### Home > CALC > Chapter 5 > Lesson 5.3.3 > Problem5-130

5-130.

OLD SOFTWARE

Old computer programs used to only allow exponentials with a certain base (like your calculator only lets you use certain types of logs). If you needed an exponential in a different base, it had to be converted first. To the right is the procedure for changing a base $2$ exponential function into base $10$. Use this technique to change $y = 3^x$ into an exponential function with base $10$.

Notice the second step of the model problem above. It is the Power Law of Logarithms; this law will become more and more necessary as this course progresses.

$y=2^x$
$\operatorname{log} y=x\operatorname{log} 2$
$y=10^{x\operatorname{log} 2}$