How do I solve the equation e^(x+3) = pi^x?

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SUMMARY

The equation e^(x+3) = pi^x can be solved by taking the natural logarithm of both sides, resulting in the equation x + 3 = x * ln(pi). By isolating x, the solution is derived as x = 3 / (ln(pi) - 1). It is crucial to remember that ln is a function and should be applied correctly to expressions, not treated as a standalone number. The discussion highlights common pitfalls in logarithmic manipulation.

PREREQUISITES
  • Understanding of natural logarithms (ln) and their properties
  • Familiarity with exponential functions and their equations
  • Basic algebraic manipulation skills
  • Knowledge of the mathematical constant pi (π) and its approximate value (3.14)
NEXT STEPS
  • Study the properties of logarithmic functions, particularly ln(x)
  • Practice solving exponential equations involving natural logarithms
  • Explore advanced topics in algebra, such as solving polynomial equations
  • Learn about the applications of logarithms in real-world scenarios
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jaypee
I'm having a hard time solving this:
e^(x+3) = pi^x


I got these results, but I'm not sure if it is correct:
ln^(x+3) = ln(pi^x)
(x+3)ln = xln(pi)
xln + 3ln = xln(pi)
3ln = xln(pi)-xln
3ln = x(ln(pi) - ln)

x = 3ln/ln(pi)-ln

NOTE: PI =3.14 (I don't know how to insert the symbol pi)
 
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That's the right way to go about, but remember, ln is a function... you have to write ln(something), ln by itself is not a number.

ln(e)=1

and you should be able to get it from there...
 
Yeah, you're kinda butchering things with your "ln raised to a power" and "ln by itself" stuff.

Step 1. Take the natural logarithm of both sides of the equation:

ln(e^(x+3)) = ln(pi^x)

this becomes

x+3 = x * ln(pi)

Step 2. Isolate x on one side of the equation

3 = x * ln(pi) - x
3 = x (ln(pi) - 1)

Step 3. Solve for x

x = 3 / (ln(pi) - 1)

- Warren
 
I'm having difficulty in solving for x,in the equation e^x=4-x^2
help please
lne^x=ln(4-x^2)
x=ln(4-x^2) and this is as far as iI got
 
Last edited:

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