Trig problems

1. Sep 19, 2012

lionely

tan 2θ= -1

I don't understand how to work this question could someone walk me through it?

ranging between -180 and 180

Last edited: Sep 20, 2012
2. Sep 19, 2012

Mentallic

For what value of x does $\tan(x)=-1$ ?

3. Sep 19, 2012

lionely

I believe -45

4. Sep 20, 2012

skiller

deleted

Last edited: Sep 20, 2012
5. Sep 20, 2012

micromass

Staff Emeritus
Is that the only value??

6. Sep 20, 2012

lionely

Yes what are the possible values of theta and I'm sure, I haven't started working in radians at school as yet... =/

7. Sep 20, 2012

Mentallic

Ok so you know that there are infinitely many solutions to tan(x)=-1 right? Because just like how the sin and cos graphs go on forever, the tan function does as well. Anyway, are you expected to find all the solution for θ between -180o and 180o?

And another thing, if tan(-45o)=-1 and we have that 2θ=-45o then what is θ?

8. Sep 20, 2012

lionely

Theta would be -22.5 oh and I forgot to mention the question asked between -180 and 180 sorry.