Use a graphing calculator to solve the following equation.

Question

Use a graphing calculator to solve the following equation.

 

 

  x

e   + In x = 9

 

what is the value of x?

 

(type an integer or a decimal rounded to the nearest hundredth as needed) 

Answer 1

e^x + ln(x) = 9

 

ln(x) = 9 - e^x

 

f(x) = ln(x)

g(x) = 9 - e^x

 

Graph and find intersection. Here's GeoGebra graph:

http://www.wyzant.com/resources/files/262897/exp_ln_graphical_solution

 

Solution is x ≈ 2.11058120966815

 

check:

 

e^(2.11058120966815) + ln(2.11058120966815) ≈? 9

 

8.253036635623706 + 0.74696336437629 ≈ 9 √