Find cos^-1x for the given x. Express your answer as a rational multiple of pi, ranging from: pi to 2pi

cos^-1 1/(sqrt)2

Question

Find cos^-1x for the given x. Express your answer as a rational multiple of pi, ranging from: pi to 2pi

cos^-1 1/(sqrt)2

dumbcow · Answer

you could use your calculator to find this.

Or use a unit circle and look for 1/sqrt(2) or sqrt(2)/2

anonymous · Answer

Well, I'm not sure how to put it into the calculator.

dumbcow · Answer

do you have a scientific calculator ... does it have trig functions on it

anonymous · Answer

Yes, it does.

dumbcow · Answer

ok cos^-1  is the inverse cosine  .... it should be above the cosine button
Use "2nd" button , then hit cosine
Enter 1/sqrt(2) 
Make sure you are in degree mode

anonymous · Answer

Awesome, thank you