Question

Please help!
Use a sketch to find the exact value of the expression:
sin[cos^-1(square root 2/2)]

Answer 1

\[\frac {\sqrt 2}{2} = \frac {1}{\sqrt 2}\]

what's cos^-1(1/sqrt2) ?

Answer 2

using the calculator I get .7854, is this the exact value for the question?

Answer 3

do you know that sin(45degrees) = cos(45degrees) = 1/sqrt2 ??

This is one of the standard values you should remember actually.

Answer 4

I do, but it has been many years and I am trying to remember the process.

Answer 5

Well, cos or sin inverse of x is that angle for which the cos or sin value is x.

Answer 6

So then the angle on the unit circle corresponds to \[\pi/4\]

Answer 7

Yes, exactly!!!

Answer 8

Great! Thanks!

Answer 9

No worries! :)