To find the derivative of (3x-5)^4, we can use the chain rule.

Let u = 3x-5.

Taking the derivative of u with respect to x, we get:

du/dx = 3

Now, we can rewrite the original function as u^4.

Using the chain rule, the derivative of u^4 with respect to x is:

d/dx (u^4) = 4u^3 * du/dx

Substitute back in u = 3x-5 and du/dx = 3:

d/dx (3x-5)^4 = 4(3x-5)^3 * 3

Simplifying this expression, we get:

d/dx (3x-5)^4 = 12(3x-5)^3

Therefore, the derivative of (3x-5)^4 is 12(3x-5)^3.