My cousin is so stubborn ____to change his mind.
方程根的情况是x2+kx-1=0根的情况是 ( )
z-是z的共轭复数,若z+z-=3,(z﹣z-)=3i(i为虚数单位),则z的实部与虚部之和为( )
你饿了,可以说: