Question

Which of the following is an irrational number? √12/√3 √18/√2 √45/√5 √42/√7

Answer 1

Answer:

√12/√3 √18/√2 √45/√5 √42/√7

Step-by-step explanation:

All are irrational number because these numbers can not be expressed in the form of p/q where p and q are integers and q is not equal to 0 ( rational numbers).

Answer 2

Answer:

only no 4 is irrational, rest all are rational

Step-by-step explanation:

1. $\frac{ \sqrt{12} }{ \sqrt{3} } = \frac{ \sqrt{4 \times 3} }{ \sqrt{3} } = \sqrt{4 } = 2$
2. $\sqrt{ \frac{18}{2} } = \sqrt{9} = 3$
3. $\sqrt{ \frac{45}{5} } = \sqrt{9} = 3$
4. $\sqrt{ \frac{42}{7} } = \sqrt{6}$

Hence only no 4 is irrational, rest all are rational