# Thread: secant / cosine functions

1. ## secant / cosine functions

I know this may seem pretty basic but I really don't understand how to estimate these values. I need to know more about the process than just the answers, thanks!

sec 67.43 = ?

If csc θ = 3.164, then θ=?

2. Originally Posted by kevin11
I know this may seem pretty basic but I really don't understand how to estimate these values. I need to know more about the process than just the answers, thanks!

sec 67.43 = ?

If csc θ = 3.164, then θ=?
hi

are you allowed to use the calculator ?

sec 67.43 = 1/ (cos 67.43) = 1/0.3838 = 2.61

csc θ = 1/ sin θ

sin θ = 1/3.164 = 0.316

θ = arc sin 0.316 (Press shift , then cos 0.316 )

3. ok thanks for your reply, and yes we are allowed to use calculators. But I'm not sure what you mean by 'θ = arc sin 0.316 (Press shift , then cos 0.316 )'. is that the sin with the little -1 (sin^-1(0.316))?

Also, is there a way to express this in terms of pi?

4. Originally Posted by kevin11
ok thanks for your reply, and yes we are allowed to use calculators. But I'm not sure what you mean by 'θ = arc sin 0.316 (Press shift , then cos 0.316 )'. is that the sin with the little -1 (sin^-1(0.316))? Yes

Also, is there a way to express this in terms of pi?
To express in terms of pi , you have to convert something in degrees to radian form and it can be done by multiplying pi/180

say to convert 30 degrees to rad form ,

30 x pi/180 = pi/6

5. Cool thanks. I didn't realize 1/sin had to be done first before using the arc sin. Probably will have more probs tomorrow, thanks again!