Question

Can someone explain this problem to me?

tan(-20°) = -tan20°

True- The answer is true, but I dont know why.
False

Answer 1

ok let`s try
can you tell sin(-x) = ? (in terms of sin(x))

Answer 2

umm Im not sure

Answer 3

anyways try...tell whatever is in your mind

Answer 4

sin(180 -) = sin

Answer 5

ok so sin(-x) = - sin(x) (clear ?)

Answer 6

okay

Answer 7

now try for cos(-x) = ?

Answer 8

okay

cos(-x)=-cos(x)

Answer 9

NO!!

Answer 10

cos(-x)=cos(x)

Answer 11

so now on right track
so tan(-x) = sin(-x)/ cos(-x)
= -sin(x)/ cos(x) = - tan(x)
do you get it now?

Answer 12

yes, I believe so

Answer 13

why are you still not sure what`s the confusion?

Answer 14

Im saying I believe so, because Im new to this so im not going to know this, but I believe I know enough to get through this lesson

Answer 15

ok so does that end this question or there is still something that you need to ask?

Answer 16

No Im good, Thank you for your time!

Answer 17

:)