Question

whats the difference in cos and -cos like in this : cos(-35°) = -cos35°

Answer 1

Hey!

Answer 2

hey

Answer 3

what do you know about `sin` and `cos` functions ?

Answer 4

i know enough about it.... its just im not sure where the -cos angle is on the graph

Answer 5

familiar with unit circle ?

Answer 6

no

Answer 7

thats okay,
do you know how to locate a point, like, (2, 3) on coordinate grid ?

Answer 8

yes

Answer 9

good, basically `cos` is the `x` coordinate of a point on unit circle.

Answer 10

for example, below length in blue color represents the value of `cos(35)` :

Answer 11

Notice that the same length also represents the value of `cos(-35)` :