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一、以复数的概念为考点,考查复数的基础知识例1设复数i满足i(z+1)=-3+2i(i是虚数单位),则z的实部是__。解析:由i(z+1)=-3+2i得到z=-3+2i/i-1=2+3i-1=1+3i。故填1。点评:本题主要考查复数的概念和四则运算。例2已知复数z=(a~2-1)+(a-2)i,(a∈R),则“a=1”是“z为纯虚数”的()。A.充分非必要条件B.必要非充分条件C.充要条件D.非充分非必要条件解析:若a=1,则z=-i为纯虚数;若z为纯虚
First, take the concept of plurals as the test point, and examine the basic knowledge of complex numbers. Example 1 Let the complex number i satisfy i(z+1)=-3+2i (i is an imaginary unit), then the real part of z is __. Resolution: z=-3+2i/i-1=2+3i-1=1+3i is obtained from i(z+1)=-3+2i. So fill in 1. Comments: This question mainly examines the concept of plural numbers and four arithmetic operations. Example 2 knows the complex number z = (a ~ 2-1) + (a - 2) i, (a ∈ R), then “ a = 1 ” is (“ z is pure imaginary ”). A. Sufficient non-essential conditions B. Necessary non- sufficient conditions C. Sufficient and necessary conditions D. Insufficient non-necessary conditions Resolution: If a = 1, then z = -i is pure imaginary number; if z is pure virtual