Question

how do you solve arctan[tan(-7pi/9)] ?

Answer 1

-7pi/9

Answer 2

isn't it outside of the domain?
So you have to find another angle...

Answer 3

arctan( tan x)=x

Answer 4

\[\tan^{-1}(\tan(x))=x\]
arctan and tan are inverses

Answer 5

yea

Answer 6

the answer has to be within the domain\[-\pi/2\le \theta lepi/2\]

Answer 7

?

Answer 8

thats not the domain of tangent. the domain of tangent is all reals except k*pi/2, where k is an integer

Answer 9

oh, you want the reference angle

Answer 10

i see

Answer 11

yes please!

Answer 12

so the answer would be 2pi/9?

Answer 13

lol im sleepy, my brain is not working right now

Answer 14

gotcha lol same here. the reference angle would be in the first quadrant yes? and the angle would be 2pi/9

Answer 15

but wouldn't it have to be positive for an angle of -7pi/9 to exist? so the original angle would be in the third quadrant