Question

If \( f(x) \) is continuous and \( \int_0^9 f(x) \, dx = 4 \), then the value of the integral \( \int_0^3 x \cdot f(x^2) \, dx \) is: (a) 2

• A. 2
• B. 18
• C. 16
• D. 4

Hint:

When dealing with integrals involving transformations such as \( x^2 \), always use substitution to simplify the integral into a standard form.