Solveeit Logo

Question

Question: \(\lim_{x \rightarrow 3}\frac{x - 3}{\sqrt{x - 2} - \sqrt{4 - x}}\) equals...

limx3x3x24x\lim_{x \rightarrow 3}\frac{x - 3}{\sqrt{x - 2} - \sqrt{4 - x}} equals

A

1

B

32\frac{3}{2}

C

14\frac{1}{4}

D

None of these

Answer

None of these

Explanation

Solution

limx3x3x24x=limx3(x3)(x2+4x)(x2)2(4x)2\lim_{x \rightarrow 3}\frac{x - 3}{\sqrt{x - 2} - \sqrt{4 - x}} = \lim_{x \rightarrow 3}\frac{(x - 3)\left( \sqrt{x - 2} + \sqrt{4 - x} \right)}{\left( \sqrt{x - 2} \right)^{2} - \left( \sqrt{4 - x} \right)^{2}}

=limx3(x3)(x2+4x)(2x6)\lim_{x \rightarrow 3}\frac{(x - 3)\left( \sqrt{x - 2} + \sqrt{4 - x} \right)}{(2x - 6)}= limx3x2+4x2=1+12=1\lim_{x \rightarrow 3}\frac{\sqrt{x - 2} + \sqrt{4 - x}}{2} = \frac{1 + 1}{2} = 1