Find the domain and range of the following functions:
(a)y=secx

Question

Find the domain and range of the following functions:
(a)y=secx

uri · Answer

K.

anonymous · Answer

$$x \neq \frac{ \Pi }{ 2 }, \frac{ 3\Pi }{ 2 }, \frac{ 5\Pi }{ 2 }, . . . . . . .$$
$$range : y \ge 1 and  y \le -1$$

hba · Answer

Ahm @yaho021 
Domain=R-{x=n(pi/2)} Where pi=1,3,5........

Couldn't get the range thing :/

hba · Answer

How do we determine the range ?

parthkohli · Answer

$$\sec(x) = \dfrac{1}{\cos(x)}$$The range of values is $(\infty , -\infty)$.

parthkohli · Answer

I may be wrong... let's see

hba · Answer

Everyone is confusing me :/

parthkohli · Answer

No, I meant when $\cos(x)$ tends to $0$ from the right side, then $\sec(x) $ goes towards $\infty$. And when it tends to $0$ from the left, then $\sec(x)$ goes towards $
-\infty$.

parthkohli · Answer

So the range is all real numbers.

hba · Answer

Okay someone said it would be All real numbers-(-1,1)

parthkohli · Answer

That's the range of $\cos(x)$, not $\sec(x)$

parthkohli · Answer

Think about the range of $\dfrac{1}{x}$. Whenever $x$ is near zero, $\dfrac{1}{x}$ is near infinity.

parthkohli · Answer

$$\dfrac{1}{0.0000001} = 1000000$$

hba · Answer

@Mimi_x3  lol so true :p

parthkohli · Answer

YAY! I was right! 

I thought I'd make a fool of myself