f(x) = x^2+2/x-3
а) f'(x) = (x^2+2/x-3)' = 2x-2x^{-2}
б) f'(4) = 2*4 - 2*4^{-2}=8- \frac{1}{8} =7 \frac{7}{8}
f(x) = x^2+2/x-3
а) f'(x) = (x^2+2/x-3)' = 2x-2x^{-2}
б) f'(4) = 2*4 - 2*4^{-2}=8- \frac{1}{8} =7 \frac{7}{8}