Question

1. Simplify the following a) 4√12 - √50 -5√48 b) √8 × √5 ×√10 c) √45 + √180 + √80

Answer 1

Answer:

1. -12√3 - 5√2
2. 20
3. 13√5

Step-by-step explanation:

1.

$4\sqrt{12}-\sqrt{50}-5\sqrt{48}\\\\4\sqrt{12}=8\sqrt{3}\\\\\sqrt{50}=5\sqrt{2}\\\\5\sqrt{48}=20\sqrt{3}\\\\=8\sqrt{3}-5\sqrt{2}-20\sqrt{3}\\\\\mathrm{Add\:similar\:elements:}\:8\sqrt{3}-20\sqrt{3}=-12\sqrt{3}\\\\=-12\sqrt{3}-5\sqrt{2}$

2.

$\sqrt{8}\sqrt{5}\sqrt{10}\\\mathrm{Apply\:radical\:rule}:\quad \sqrt{a}\sqrt{b}=\sqrt{a\times b}\\\\=\sqrt{8\times \:5\times \:10}\\\\=\sqrt{400}\\\\\mathrm{Factor\:the\:number:\:}\:400=20^2\\\\=\sqrt{20^2}\\\\\mathrm{Apply\:radical\:rule}:\quad \sqrt[n]{a^n}=a\\\\\sqrt{20^2}=20$

3.

$\sqrt{45}+\sqrt{180}+\sqrt{80}\\\\\sqrt{45}=3\sqrt{5}\\\\\sqrt{180}=6\sqrt{5}\\\\\sqrt{80}=4\sqrt{5}\\\\=3\sqrt{5}+6\sqrt{5}+4\sqrt{5}\\\\\mathrm{Add\:similar\:elements:}\:3\sqrt{5}+6\sqrt{5}+4\sqrt{5}\\\\=13\sqrt{5}$