定义：如果一个数的平方等于－1，记为 i2=−1 ，数 i 叫做虚数单位．我们把形如 a+bi （ a , b 为有理数或无理数）的数称为复数，它的加，减，乘法运算与整式的加，减，乘法运算类似.例如：_刷题宝

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定义：如果一个数的平方等于－1，记为 i2=−1 ，数 i 叫做虚数单位．我们把形如 a+bi （ a , b 为有理数或无理数）的数称为复数，它的加，减，乘法运算与整式的加，减，乘法运算类似.例如：计算 (2+3i)(3−2i)=6−4i+9i−6i2=6+5i+6=12+5i ，计算 (−3+4i)(3+4i) ＝____.

上一题下一题 0.0难度选择题更新时间:2013-07-18 04:03:26

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－25

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