Question

According to my book, tan(-6pi) = tan 0 = 0.

My calculator disagrees and gives tan(-6pi) = -0,34

Help?

Answer 1

Is your calculator in radian mode?

Answer 2

make sure you're in radian mode

Answer 3

You're both right, I wasn't in radian mode. But that just makes things weirder, not tan (-6*pi) = 2e^-13

Answer 4

* "...weirder, now tan (-6*pi) = 2e^-13"

Answer 5

well if you were you degree mode, then

tan(-2pi) = -tan(2pi)

tan(-2pi) = -tan(2*3.14)

tan(-2pi) = -tan(6.28)

tan(-2pi) = -0.11004772101689

So that's what you should have gotten IF you were you degree mode

Answer 6

oh sry I did 2pi on accident, let me fix

Answer 7

if you were you degree mode, then

tan(-6pi) = -tan(2pi)

tan(-6pi) = -tan(6*3.14)

tan(-6pi) = -tan(18.84)

tan(-6pi) = -0.3412069928076

So that's what you should have gotten IF you were you degree mode

Answer 8

**now tan (-6*pi) = 2e^-13

2 times 10^-13 is a tiny number. It is not zero because your calculator does not have enough digits to do this problem accurately. But for practical purposes 2e-13 is close enough to zero.

Answer 9

although my calculator comes up with 0.

Answer 10

allright, I see, thanks!