**Find one positive and one negative angle coterminal with an angle of 9π/6**

**Answer:**

Take first angle to be -9π/12 so the second angle obviously becomes 9π/12. And their difference = 9π/12 - (- 9π/12) = 9π/6.

**Find one positive and one negative angle coterminal with an angle of 9π/6**

**Answer:**

Take first angle to be -9π/12 so the second angle obviously becomes 9π/12. And their difference = 9π/12 - (- 9π/12) = 9π/6.