If latex: \{a_i: i\in i\} is a collection of open subsets of latex: \mathbb{r} , then latex: \cup_{i\in i}a_i is open in latex: \mathbb{r}

(can this be proved without the concept of the open ball from topology)

i = 2 / - 5

step-by-step explanation:

evaluation of ( 2 - 4 ) ( p + q ) when p = 2 and q = 5 i, by putting values of p and q,                                                                    

a

step-by-step explanation:

what is the information provided?

step-by-step explanation: