Scatter plot, equation of exponential function

[pbonnie]

Homework Statement

The copy of the question is in the image attached. I don't have a graphing calculator, and so am not sure how to determine the equation of the exponential function.

Homework Equations

y = a^x

The Attempt at a Solution

I made a scatter plot off of an online program (image also attached) but am unsure how to proceed. I could not find an online graphing calculator that could determine the equation.

 

[rock.freak667]

You can try to use microsoft excel to plot the graph and give you the equation of the trend.

If you need to show how to calculate the exponential function, you will need to lookup exponential regression lines.

 

[pbonnie]

How would I find the equation that way?

 

[rock.freak667]

How would I find the equation that way?

http://mathworld.wolfram.com/LeastSquaresFittingExponential.html

this link should help.

However since the questions are meant to be done on a computer/calculator, just do a scatter plot in excel, right click on a point and add a trend line, then just change it to exponential.

 

[pbonnie]

Okay great, thanks. I got the line of best fit - exponential, and it added an equation in the form y = A e^bx. But I'm not sure what that means. What is the "e" in the equation? and since the "bx" are both superscript, do you multiply them?

 

[rock.freak667]

Okay great, thanks. I got the line of best fit - exponential, and it added an equation in the form y = A e^bx. But I'm not sure what that means. What is the "e" in the equation? and since the "bx" are both superscript, do you multiply them?

e is a mathematical constant like pi.

e ≈ 2.718281818...

the x is your independent variable. If A=2 and b=3, then your equation is y=2e^3x.

 

[pbonnie]

Oh okay. So if it came out with the equation y = 11246 e^0.291x, how would that be written to give the answer for the question b?

 

[rock.freak667]

Oh okay. So if it came out with the equation y = 11246 e^0.291x, how would that be written to give the answer for the question b?

It would be written exactly like that, you would just need to define what 'y' represents and what 'x' represents.

 

[pbonnie]

Oh. Okay thank you very much!