Question

Help please ?

Answer 1

sure

Answer 2

you are looking for the number between 0 and \(\pi\) whose cosine is \(\frac{1}{2}\)

Answer 3

if you still have that cheat sheet, look at the place on the upper half of the unit circle where the second coordinate is \(\frac{1}{2}\)

Answer 4

π/3 simple

Answer 5

:)

Answer 6

ok here is the picture

Answer 7

in this picture, \(\theta=\arctan(2)\) an angle whose tangent is 2
since tangent is "opposite over adjacent" i labelled the opposite side 2 and the adjacent side 1

Answer 8

the hypotenuse we find by pythagoras, it is \(\sqrt{1^2+2^2}=\sqrt{1+4}=\sqrt{5}\)

Answer 9

and using sine as "opposite over hypotenuse" we see that the sine of the angle is
\[\frac{2}{\sqrt{5}}\]