Answer:
2
Explanation:
Remark
Treat that i as though it were any letter used as variable. The fact that it represents the square root of minus 1 is not an issue here. If you have 5x -5x the result is 0.
Same thing with this question
u + v = 1 + i + 1 - i = 2 The two "i"s cancel and the two "1"s add. The answer is 2