Q. \[ \int 3^{x}\,dx \]
Answer
We use the rule \(\int a^x\,dx=\dfrac{a^x}{\ln a}+C\) for \(a>0\), \(a\ne 1\). Here \(a=3\).
\[
\int 3^x\,dx=\frac{3^x}{\ln 3}+C
\]
Detailed Explanation
We want to compute the indefinite integral
\[
\int 3^{x}\,dx
\]
Step 1: Recall the rule for integrating an exponential of the form \(a^{x}\).
A standard result is:
\[
\int a^{x}\,dx=\frac{a^{x}}{\ln(a)}+C \quad \text{for } a>0,\ a\neq 1
\]
Here, \(a=3\), so \(\ln(3)\) will appear in the denominator.
Step 2: Substitute \(a=3\) into the formula.
\[
\int 3^{x}\,dx=\frac{3^{x}}{\ln(3)}+C
\]
Step 3: (Optional check by differentiating.)
Differentiate the result:
\[
\frac{d}{dx}\left(\frac{3^{x}}{\ln(3)}\right)=\frac{1}{\ln(3)}\cdot \frac{d}{dx}\left(3^{x}\right)
\]
Using \(\frac{d}{dx}\left(3^{x}\right)=3^{x}\ln(3)\):
\[
\frac{1}{\ln(3)}\cdot \left(3^{x}\ln(3)\right)=3^{x}
\]
This matches the integrand, so the answer is correct.
Final Answer:
\[
\int 3^{x}\,dx=\frac{3^{x}}{\ln(3)}+C
\]
Calculus FAQ
What is \( \int 3^x\,dx \)?
How do you use the rule \(\int a^x\,dx\) with \(a=3\)?
Why does a \(\ln 3\) appear in the answer?
What is \( \int 5^x\,dx \)?
What is \( \int 2\cdot 3^x\,dx \)?
What is \( \int 3^{2x}\,dx \)?
Use tools to check your work.
Math, Geometry, Trigonometry, etc.