Question

A equação da reta tangente à f(x)=x−2x no ponto (1,−1) é:

Answer 1

$\large\boxed{\begin{array}{l}\rm f(x)=x-\dfrac{2}{x}\\\\\rm f'(x)=1+\dfrac{2}{x^2}\\\\\rm f'(1)=1+\dfrac{2}{1^2}\\\\\rm f'(1)=1+2=3\\\\\rm y=y_0+f'(x_0)(x-x_0)\\\rm y=-1+3(x-1)\\\rm y=-1+3x-3\\\rm y=3x-4\end{array}}$