Which numbers in the following set are irrational numbers? $$\left\{ \frac { 1 } { 9 } , 7 , \sqrt { 7 } , \pi , - 0.4 \right\}$$
A) $\sqrt { 7 } , \pi$
B) $\sqrt { 7 } , \pi , - 0.4$
C) $\frac { 1 } { 9 } , 7 , \sqrt { 7 } , \pi , - 0.4$
D) $\frac { 1 } { 9 } , 7 , - 0.4$

Question

Quizplus · Accepted Answer

$\sqrt{7}$ and $\pi$ are irrational because they cannot be expressed as a fraction of two integers and their decimal expansions are non-repeating and non-terminating.

Which Numbers in the Following Set Are Irrational Numbers {19,7,7,π,−0.4}\left\{ \frac { 1 } { 9 } , 7 , \sqrt { 7 } , \pi , - 0.4 \right\}{91​,7,7​,π,−0.4}

Which Numbers in the Following Set Are Irrational Numbers $\left\{ \frac { 1 } { 9 } , 7 , \sqrt { 7 } , \pi , - 0.4 \right\}$