A:x2+x4=x6
B:(−x3)2=x6
C:2a+3b=5ab
D:x6÷x3=x2(x≠0)
I need a pair of _______.
虚数(x-2)+yi中x,y均为实数,当此虚数的模为1时,yx的取值范围是( )