# Square and Cube Roots Quiz Set 018

### Question 1

What is the value of \$√{3 + √1}\$?

A

2.

B

√3.

C

1.

D

4.

Soln.
Ans: a

The given expression is same as \$√{3 + √1^2}\$, which becomes \$√{3 + 1}\$, or \$√4\$ which gives 2 as the answer. Please note that squares of as many numbers should be always on your tips.

### Question 2

What is the value of \$√{(22 - 4√2) × (22 + 4√2)}\$?

A

\$√452\$.

B

\$√22\$.

C

\$√2\$.

D

\$√11\$.

Soln.
Ans: a

By inspection, we can easily see that the formula (a - b) × (a + b) can be used to simplify like this: \$√{(22)^2 - (4√2)^2}\$, which is same as \$√{484 - (4^2 × 2)}\$, which is same as \$√{484 - 32}\$ = \$√452\$.

### Question 3

One-fourth of the square-root of which number is 0.7?

A

7.84.

B

8.64.

C

8.49.

D

6.64.

Soln.
Ans: a

Let the number be n. So \${1/4} × √n\$ = 0.7, which gives \$√n\$ = 4 × 0.7 = 2.8. so n = \$2.8^2\$ = 7.84.

### Question 4

If x = 0.7968, then what is the value of \$4x + √{16x^2 - 8x + 1}\$?

A

1.

B

16.

C

8.

D

2.

Soln.
Ans: a

By inspection, \$4x + √{16x^2 - 8x + 1}\$ is same as \$4x + √{({1 - 4x})^2}\$, which is same as 4x + (1 - 4x) = 1.

### Question 5

What is √0.0081?

A

0.09.

B

0.9.

C

0.009.

D

0.0009.

Soln.
Ans: a

We can see that 0.09 × 0.09 = 0.0081, so square root is 0.09. This Blog Post/Article "Square and Cube Roots Quiz Set 018" by Parveen (Hoven) is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Updated on 2020-02-07. Published on: 2016-04-20