The E symbol is used for entering numbers in scientific notation.

*mantissa* E *exponent*

Press [2nd][EE] to paste the E command.

TI-83/84/+/SE

1 byte

The `E` symbol is used for entering numbers in scientific notation: it's short for *10^. This means that in many cases, its function is identical to that of the `10^(` command (aside from the parenthesis). However, the exponent of `E` is limited to constant integer values ‾99 to 99.

The `E` symbol is used in display by the calculator for large numbers, or when in `Sci` (scientific) or `Eng` (engineering) mode.

Unlike the exponent of `E`, the mantissa (a special term for the A in A*10^B, in scientific notation) isn't limited in variable type: it can be a constant, a real or complex variable or expression, a list, a matrix, or even omitted entirely (and then it will be assumed to equal 1). The reason for this versatility is simple: internally, only the exponent is taken to be an actual argument for this command. The rest of the calculation is done through implied multiplication.

5E3

………………5000

E‾5

……………….00001

# Advanced Uses

`E`99 and -`E`99 are often used for negative and positive infinity because the TI-83 series of calculators doesn't have an infinity symbol. Commands that often need to use infinity include `solve(`, `fnInt(`, `normalcdf(` (and the other distributions), and many others. The error introduced in this way is usually irrelevant, because it's less than the minimum calculator precision, anyway: `E`99 is mindbogglingly huge.

# Optimization

Don't add the mantissa when it's 1:

1E5

should be

E5

In addition, `E`2 or `E`3 can be used as shorthand ways of writing 100 and 1000 respectively. This could be continued, in theory, for higher powers of 10, but those aren't necessary as often.

# Command Timings

`E` is much faster than using the `10^(` command or typing out 10^. The drawback, of course, is that it's limited to constant values.

# Related Commands

.