This is the question:

Find the numbers(s) x in the interval [0, 2Pi] which satisfies the equation,

tan x / 2 = 1

I multiplied both sides by 2, and solved for x using my calculator:

tan x = 2

x = 63.43

However, the answer is Pi/2. What have I done wrong? 63.43 degrees is a long shot from 90 degrees. :/