Question

Find the exact value of the expression.
sec [ sin^-1 (-(√3)/2)]

Answer 1

lets find the value of sin^-1 (-(√3)/2) first,
let \(\sin^{-1} (-(√3)/2) = y \)
so,
\(-\sqrt3/2=\sin y\)
do you know for which angle, value of sin y is -(√3)/2 ?

Answer 2

5π/3 or 4π/3? o:

Answer 3

you can use any value, you'll get the same answer in the end ^_^

Answer 4

so, sec [..that angle...] =... ?

Answer 5

Uhh, I'm not sure o;

Answer 6

ok, its y=5pi/3
so, sec[5pi/3] =... ?

Answer 7

1/2?

Answer 8

1/2 or 2 ?

Answer 9

Should I be putting it in the calculator? Or looking at the unit circle o;

Answer 10

if you can use calculator, then its great...just plug in that

Answer 11

It keeps saying error o: Let me try a different one

Answer 12

if you can use internet resources, you can always use google :
https://www.google.co.in/search?hl=en&newwindow=1&q=sec+%285pi%2F3%29&oq=sec+%285pi%2F3%29&gs_l=serp.3...4789.4815.0.4847.6.1.0.0.0.0.0.0..0.0...0.0...1c.1.7.serp.gMaYfdw85V8

Answer 13

I can't on the test o; Why does it keep saying domain error?

Answer 14

what did you plug in calculator exactly ?

Answer 15

cos^-1 (5π/3)

Answer 16

why! ?

sec [ sin^-1 (-(√3)/2)]
we let y=sin^-1 (-(√3)/2)
so, we need to find sec y
we got y= 5pi/3
so, we just need sec (5pi/3)
did you get this ?

Answer 17

Yess, cos^-1 is the same as sec o;

Answer 18

not at all!

Answer 19

cos^-1 is not sec...if you want sec you have to put 1/[cos(x)]

Answer 20

\(\cos x = 1/\sec x\)
so, you try \(1/\cos[5\pi/3]\)

Answer 21

And then I get 1.0042

Answer 22

Change the mode...you have it in degree mode right now. It needs to be in radian

Answer 23

Oo okay! Thank you guys very much (:

Answer 24

welcome ^_^