Question

f(x)=x-5/x,x=2 найдите производную

Answer 1

Ответ на фото/////////////

Answer 2

$f(x)=\frac{x-5}{x}=\frac{x}{x}-\frac{5}{x}=1-\frac{5}{x}\\\\\star \; \; (\frac{u}{v})'=\frac{u'v-uv'}{v^2}\; \; ,\; \; C'=0\; \; (C=const)\; \; \star \\\\f'(x)=1'-\frac{-5\cdot x'}{x^2}=0+\frac{5}{x^2}=\frac{5}{x^2}\\\\f'(2)=\frac{5}{2^2}=\frac{5}{4}=1,25$