题目内容
16.复数z=x+yi(x,y∈R),且2x+y+ilog2x-8=(1-log2y)i,求z.分析 根据复数相等的条件建立方程关系进行求解即可.
解答 解:∵2x+y+ilog2x-8=(1-log2y)i,
∴$\left\{\begin{array}{l}{{2}^{x+y}-8=0}\\{lo{g}_{2}x=1-lo{g}_{2}y}\end{array}\right.$,即$\left\{\begin{array}{l}{{2}^{x+y}=8}\\{lo{g}_{2}x+lo{g}_{2}y=lo{g}_{2}xy=1}\end{array}\right.$,
则$\left\{\begin{array}{l}{x+y=3}\\{xy=2}\end{array}\right.$,则$\left\{\begin{array}{l}{x=2}\\{y=1}\end{array}\right.$或$\left\{\begin{array}{l}{x=1}\\{y=2}\end{array}\right.$,
即z=1+2i或z=2+i.
点评 本题主要考查复数的计算,根据复数相等建立方程组求出x,y是解决本题的关键.
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