Find the Domain and Range y=2sec(x)

$y = 2 \sec (x)$

Step 1

Set the argument in $\sec (x)$ equal to $\frac{π}{2} + π n$ to find where the expression is undefined.

$x = \frac{π}{2} + π n$ , for any integer $n$

Step 2

The domain is all values of $x$ that make the expression defined.

Set-Builder Notation:

${x | x \neq \frac{π}{2} + π n}$ , for any integer $n$

Step 3

The range is the set of all valid $y$ values. Use the graph to find the range.

Interval Notation:

$(- \infty, - 2] \cup [2, \infty)$

Set-Builder Notation:

${y | y \leq - 2, y \geq 2}$

Step 4

Determine the domain and range.

Domain: ${x | x \neq \frac{π}{2} + π n}$ , for any integer $n$

Range: $(- \infty, - 2] \cup [2, \infty), {y | y \leq - 2, y \geq 2}$

Step 5