F'(x) = (x⁴)' - 4(x³)' + 6(x²)' - 7' = 4x³ - 12x² + 12x
f'(x) = 7(x⁵)' - 9(x³)' + 3(x)' - (3,5)' = 35x⁴- 27x² + 3
f'(x) = (x³ - 2x)' * ( x² + 3) + (x³ - 2x) * (x² + 3)' = (3x² - 2)(x² + 3) +
+ (x³ - 2x) * 2x = 3x⁴ + 9x² - 2x² - 6 + 2x⁴ - 4x² = 5x⁴ +3x² - 6