Question

What is the exact value of the expression the square root of 72 − the square root of 8 + the square root of 128?

Answer 1

The answer is
$12 \times \sqrt{2}$

Answer 2

Answer:

Option B is correct.

Step-by-step explanation:

Given Expression is $\sqrt{72}-\sqrt{8}+\sqrt{128}$

Simplify the given expression,

72 = 2 × 2 × 2 × 3 × 3                 ⇒ √72 = 6√2

8 = 2 × 2 × 2                               ⇒ √8 = 2√2

128 = 2 × 2 × 2 × 2 × 2 × 2 × 2   ⇒ √128 = 8√2

⇒  $\sqrt{72}-\sqrt{8}+\sqrt{128}=6\sqrt{2}-2\sqrt{2}+8\sqrt{2}$

    $=12\sqrt{2}$

Therefore, Option B is correct.