Questions: Use the substitution formula to evaluate the integral.
∫ from 0 to 1 sqrt(x+9) dx
Transcript text: Use the substitution formula to evaluate the integral.
\[
\int_{0}^{1} \sqrt{x+9} d x
\]
Solution
Solution Steps
Step 1: Substitution
Let \( u = x + 9 \). Then, the differential \( du = dx \). We also need to change the limits of integration: when \( x = 0 \), \( u = 9 \) and when \( x = 1 \), \( u = 10 \).
Step 2: Rewrite the Integral
The integral can now be rewritten as:
\[
\int_{0}^{1} \sqrt{x+9} \, dx = \int_{9}^{10} \sqrt{u} \, du
\]
Step 3: Evaluate the Integral
Using the power rule for integration, we find:
\[
\int \sqrt{u} \, du = \frac{2}{3} u^{3/2}
\]
Thus, we evaluate:
\[
\left[ \frac{2}{3} u^{3/2} \right]_{9}^{10} = \frac{2}{3} (10^{3/2}) - \frac{2}{3} (9^{3/2})
\]
Calculating this gives:
\[
\frac{2}{3} (10\sqrt{10} - 27)
\]
This simplifies to:
\[
-18 + \frac{20\sqrt{10}}{3}
\]