If R_1 = {(x, y) | y = 2x + 7, where x ∈ R and – 5 ≤ x ≤ 5} is a relation. Then find the domain and Range of R_1.
If R_1 = {(x, y) | y = 2x + 7, where x ∈ R and – 5 ≤ x ≤ 5} is a relation. Then find the domain and Range of R_1.

Solution:

Provided,

R_1 =\{(x, y) \mid y=2 x+7, in which x ∈R and {-} 5\leq x\leq 5} is a relation

All the first elements of all the ordered pairs of R_1, i.e., x, are included in the domain of R_1

Also provided -5 \leq x \leq 5.

As a result,

Domain of R_1 = [{-}5, 5]

All the second elements of all the ordered pairs of R_1, i.e., y, are included in the range of R.

Also provided y = 2x + 7

So now, \mid x \in[-5,5]

Now multiply both L.H.S. and R.H.S. by 2,

We have,

2 \times \in[-10,10]

Now add L.H.S. and R.H.S. with 7,

We have,

2 x+7 \in[-3,17

Or, y \mid \in[-3,17]

Therefore,

Range of R_1 = [{-}3, 17]