Verified answer

a) f(x) = 4x - 5x²

f'(x) = 4 - 10x

при х = 1    f'(1) = 4 - 10 = -6

б) f(x) = 2x⁵ - 3x³ + 1

f'(x) = 10x⁴ - 9x²

при х = -1     f'(-1) = 10 - 9 = 1

в) f(x) = (x - 3)(x + 3) - 9

f(x) = x² - 9 - 9

f(x) = x² - 18

f'(x) = 2x

при х = 0,5   f'(0,5) = 2· 0,5 = 1

г) f(x) = (x - 5)/x

f'(x) = (1 · x - 1·(x - 5))/x²

f'(x) = (x - x + 5)/x²

f'(x) = 5/x²

при х = 2    f'(2) = 5/4 = 1,25