Question

Find the approximate value of the given trigonometric function by using the following picture for...

cos(0.7)
cos(1)
tan(-2.1)
sin(-0.9)

if you can explain too that would be awesome!

Answer 1

I don't understand how that picture helps

Answer 2

all i know is its a unit circle, if that helps at all. I assume it doesnt because it makes no sense to me lol

Answer 3

So it's the unit circle, each tick mark is one-tenth of a radian.
So they've measured out the entire \(2\pi\) which is approx 6.3.

If we look where 0.7 radians is on the unit circle (3 ticks before the red 1),
the cosine is the distance we travel along the `x` direction to get to that point.

Answer 4

Understand what I'm talking about?
Look at the attached image.
The red line is drawn at an angle of 0.7 radians.
The light-blue line represents the `cosine` of our angle 0.7.

What is it's length?
Hmm it looks like it's about 3/4 of the way across that line. we can count the tick marks along the x-direction to get a better approximation.

Answer 5

yea that was insanely helpful, thanks!

Answer 6

yay c: