Proving that the integral of (a^x)dx = a^x/(lna)+c ?

  • Thread starter JJHK
  • Start date
  • Tags
    Integral
In summary, the formula for proving the integral of (a^x)dx = a^x/(lna)+c is ∫a^x dx = a^x/(lna) + c. This can be proven using the fundamental theorem of calculus and an example for a = 2 is provided. The ln(a) term in the formula represents the natural logarithm of the base, allowing for generalization to other bases. The formula can also be applied to other exponential functions as long as they follow the same form.
  • #1
JJHK
24
1
Proving that the integral of (a^x)dx = a^x/(lna)+c ?

Hi, I know that:

∫ax dx = ax / ln(a) + C

Could someone give me a step by step that proves this? thanks a lot!
 
Physics news on Phys.org
  • #2


Here's a trick:

Re-write your integral as:

[tex]

\int e^{lna*x}dx
[/tex]

Then use a substitution:

u = ln(a) * x
 
  • #3


Beautiful! Thank you :D
 

1. What is the formula for proving the integral of (a^x)dx = a^x/(lna)+c?

The formula for proving the integral of (a^x)dx = a^x/(lna)+c is:

∫a^x dx = a^x/(lna) + c

2. How do you prove the integral of (a^x)dx = a^x/(lna)+c?

To prove the integral of (a^x)dx = a^x/(lna)+c, you can use the fundamental theorem of calculus, where the derivative of the antiderivative is equal to the original function. In this case, the antiderivative of a^x is a^x/(lna), so taking the derivative of this will result in a^x. Adding a constant, c, accounts for any possible additional terms in the original function.

3. Can you provide an example of proving the integral of (a^x)dx = a^x/(lna)+c?

Yes, for example, let a = 2. Then, the integral of 2^x dx = 2^x/(ln2) + c. To prove this, we can take the derivative of 2^x/(ln2) + c, which is 2^x * ln2/(ln2) = 2^x. This matches the original function, so the integral is proven.

4. What is the significance of the ln(a) term in the formula for proving the integral of (a^x)dx = a^x/(lna)+c?

The ln(a) term in the formula represents the natural logarithm of the base, a. This is important because it allows us to generalize the formula for any base, not just the natural base, e. Without this term, the formula would only apply to integrals of the form a^x dx, where a = e.

5. Can the formula for proving the integral of (a^x)dx = a^x/(lna)+c be applied to other exponential functions?

Yes, the formula can be applied to other exponential functions as long as they follow the same basic form as a^x. This includes functions such as e^x, 3^x, and (1/2)^x. However, the ln(a) term will change depending on the base of the exponential function being integrated.

Similar threads

  • Calculus and Beyond Homework Help
Replies
5
Views
200
  • Calculus and Beyond Homework Help
Replies
14
Views
249
  • Calculus and Beyond Homework Help
Replies
7
Views
707
  • Calculus and Beyond Homework Help
Replies
8
Views
763
  • Calculus and Beyond Homework Help
Replies
3
Views
278
  • Calculus and Beyond Homework Help
Replies
3
Views
346
  • Calculus and Beyond Homework Help
2
Replies
54
Views
8K
  • Calculus and Beyond Homework Help
Replies
2
Views
842
  • Calculus and Beyond Homework Help
Replies
2
Views
877
  • Calculus and Beyond Homework Help
Replies
15
Views
787
Back
Top