1) f(x) = sin(x^2 + 3)
u(x) = sin(x)
v(x) = x^2 + 3
f'(x) = cos(x^2 + 3) * 2x
2) f(x) = (2x + 9)^4
u(x) = x^4
v(x) = 2x + 9
f'(x) = 4 * (2x + 9)^3 * 2 = 8 * (2x + 9)^3
3) f(x) = (x^2 + 1)^{1/2}
u(x) = x^{1/2}
v(x) = x^2 + 1
f'(x) = (1/2)*(x^2 + 1)^{-1/2} * 2x = x / (x^2 + 1)^{1/2}
4) f(x) = 3 * cos(3x)
u(x) = 3 * cos(x)
v(x) = 3x
f'(x) = 3 * (-sin(3x)) * 3 = -9 * sin(3x)