## pottersheep 3 years ago I need help please for this Trig equation!

1. pottersheep

How do I do tan2x = -1 between -2pi<=x<=2pi ??

2. cwrw238

first find all values of 2x whose tan = -1 in the range -4pi to 4pi then divide by 2

3. cwrw238

first find all values of 2x whose tan = -1 in the range -4pi to 4pi then divide by 2

4. pottersheep

My values dont match the teachers, well my negative values dont

5. cwrw238

|dw:1353876122189:dw|

6. cwrw238

|dw:1353876122189:dw|

7. pottersheep

Yup okay so 3pi/4 and 7pi/4

8. cwrw238

the 2 values of x between 0 and 2pi are 4p-/4 and 7pi/4 - yes

9. cwrw238

* 3pi/4

10. pottersheep

can you help me find al the values though please

11. cwrw238

values of 2x are 3pi/4,7pi/4, 3pi/4 + 2pi, 7pi/4 + 2pi, -pi/4, -5pi/4, -pi/4 - 2pi, -5p i/4- 2pi ill let you simplify some of those values of x are half of these

12. cwrw238

values of 2x are 3pi/4,7pi/4, 3pi/4 + 2pi, 7pi/4 + 2pi, -pi/4, -5pi/4, -pi/4 - 2pi, -5p i/4- 2pi ill let you simplify some of those values of x are half of these

13. pottersheep

Thank you!! That's what I got too but thats not what my teacher did so I got confused!