Question

Lim (9-x)/(3-√x), x ->9. Correct answer is 6

Answer 1

`\lim_(x\to 9)(9-x)/(3-\sqrt x)=\\ \lim_(x\to 9)((9-x)')/((3-\sqrt x)')=\\ \lim_(x\to 9)(-1)/(-(1)/(2\sqrt x))=\\ \lim_(x\to 9)2\sqrt x=\\ 2\sqrt9=\\ 2\cdot3=\\ 6`