4
4 - 3 = 1
1 - 3 = -2
-2 - 3 = -5
-5 - 3 = -8
It's the arithmetic sequence.


substitute

Answer: 
It is 7. None of the other ones fit at all
Answer:

Step-by-step explanation:
Complex numbers identity:
The complex numbers identity is:

Square of the sum:

In this question:





So

Answer: (3,1)
Explanation:
Negative 1/20 is the answer