πŸ€–
Hello Alex! πŸ‘‹ I'm your AP Calculus AB tutor. I see you're working on integration techniques today. What would you like help with?
AC
I'm stuck on integration by parts. I don't understand when to use it vs u-substitution.
πŸ€–
Great question! Let me guide you through the decision process.

Use u-substitution when you see a composite function β€” the integrand contains a function and its derivative.

Use integration by parts when you have a product of two different types of functions (like polynomial Γ— trigonometric, or polynomial Γ— exponential).

Here's a quick test: Can you identify which technique you'd use for ∫ x·eˣ dx?
AC
Integration by parts? Because it's x times e^x?
πŸ€–
Exactly right! βœ… Since xΒ·eΛ£ is a product of a polynomial (x) and an exponential (eΛ£), integration by parts is the way to go.

Remember the formula: ∫ u dv = uv - ∫ v du

For this problem, what would you choose as u and dv? (Hint: Think about which function becomes simpler when differentiated)