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

Question

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

apoorvk · Answer

$$\frac {\sqrt 2}{2} = \frac {1}{\sqrt 2}$$

what's cos^-1(1/sqrt2) ?

anonymous · Answer

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

apoorvk · Answer

do you know that sin(45degrees) = cos(45degrees) = 1/sqrt2 ??

This is one of the standard values you should remember actually.

anonymous · Answer

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

apoorvk · Answer

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

anonymous · Answer

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

apoorvk · Answer

Yes, exactly!!!

anonymous · Answer

Great! Thanks!

apoorvk · Answer

No worries! :)