Question
find the exact value:
cos^-1 (square root of 2 divided by 2)
cos^-1 (square root of 2 divided by 2)
Answers
Damon
draw a 45 45 90 triangle with equal legs = 1
hypotenuse^2 = 1^2+1^2
h^2 = 2
h = sqrt 2
then cos 45 = 1/sqrt2 = sqrt 2/2
hypotenuse^2 = 1^2+1^2
h^2 = 2
h = sqrt 2
then cos 45 = 1/sqrt2 = sqrt 2/2