You are here:

Question
hi,

I'm doing an exponential regression in excel and have been given this equation. y = 1E-19e^1.9985x
i know the 1E-19 is ten to the minus nineteen and i believe the e represents an exponential constant.

say i had an x value of 23, i don't suppose there is a chance you would know how to type this full equation into excel to work out the y i can't seem to make it work. i am hopeful your mathematical brain might fare better.

cheers

The expression can be written in Excel notation as

y = 10^(-19)*EXP(1.9985*x)

where EXP is an actual function in Excel that expects an argument (i.e., some number or cell reference) inside the parentheses.

The ∧ in the expression 10^(...) just means "raise to the power" e.g.. 10 squared would be 10∧2.

Putting the number 23 into the symbol x is a 2 step process. First put the number 23 into some convenient cell, like C1 (3rd column, first row). This can then be referenced as \$C\$1, where the \$ means always refer to the specific column or row.

so, if you want the value of y to be evaluated in the cell A1, then put into that cell the expression

= 10^(-19)*EXP(1.9985*\$c\$1)

where the "=" sign is included (in fact, it is very important to put the = sign in there so that Excel interprets what's in the cell as an expression it needs to evaluate). Copying directly from the Excel file I used, the expression for y in the cell A1 is

=10^(-19)*EXP(1.9985*\$C\$1)

and the number it produces is

9.174090245

where I put 23 into the cell C1.

Volunteer

#### randy patton

##### Expertise

college mathematics, applied math, advanced calculus, complex analysis, linear and abstract algebra, probability theory, signal processing, undergraduate physics, physical oceanography

##### Experience

26 years as a professional scientist conducting academic quality research on mostly classified projects involving math/physics modeling and simulation, data analysis and signal processing, instrument development; often ocean related

Publications
J. Physical Oceanography, 1984 "A Numerical Model for Low-Frequency Equatorial Dynamics", with M. Cane

Education/Credentials
M.S. MIT Physical Oceanography, B.S. UC Berkeley Applied Math

Past/Present Clients
Also an Expert in Oceanography