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            • 1.

              已知复数\(z=x+yi(x z=x+yi(x\)、\(y∈ R)\),且有\( \dfrac{x}{1-i}=1+yi \),则\(\left|z\right|= \)


              A.\(5\)           
              B.\( \sqrt{5} \)
              C.\(3\)
              D.\( \sqrt{3} \)
            • 2.

              已知复数\({z}_{1}=\left(2x+1\right)+2i,{z}_{2}=-x-yi\left(x,y∈R\right) \)

              \((1)\)若\({{z}_{1}}+{{z}_{2}}=0\),求\({{x}^{2}}-{{y}^{2}}\)的值;

              \((2)\)若复数\(\left(1+i\right)·{z}_{1} \)为纯虚数,求复数\({{z}_{1}}\)的模\(\left| {{z}_{1}} \right|\)。

            • 3.

              若\(x\)是纯虚数,\(y\)是实数,且\(2x-1+i=y-(3-y)i\),则\(x+y\)等于(    )

              A.\(1+ \dfrac{5}{2}i\)      
              B.\(-1+ \dfrac{5}{2}i\)    
              C.\(1- \dfrac{5}{2}i\)         
              D.\(-1- \dfrac{5}{2}i\)
            • 4.

              若\( \dfrac{1-i}{1+i}=a+bi,(a,b∈R) \),则\( \dfrac{a}{b} \)的值是 \((\)  \()\)

              A.\(1\)     
              B.\(0\)      
              C.\(-1\)     
              D.\(-2\)
            • 5.
              已知实数\(m\),\(n\)满足\((m+ni)(4-2i)=3i+5\),则\(m+n=(\)  \()\)
              A.\( \dfrac {9}{5}\)
              B.\( \dfrac {11}{5}\)
              C.\( \dfrac {9}{4}\)
              D.\( \dfrac {11}{4}\)
            • 6.
              \(i\)是虚数单位,若\( \dfrac {2+i}{1+i}=a+bi(a,b∈R)\),则\(a+b\)的值是\((\)  \()\)
              A.\(0\)
              B.\( \dfrac {1}{2}\)
              C.\(1\)
              D.\(2\)
            • 7.

              满足\(z+\dfrac{10}{z}\)是实数,且\(z+4\)的实部与虚部相等的虚数\(z\)是否存在\(?\)若存在,求出虚数\(z\);若不存在,请说明理由.

            • 8.

              已知\(=2-2\)\(i\)\((\)\(i\)为虚数单位\()\),则实数\(b\)\(=\)(    )

              A.\(3\)
              B.\(-6\)
              C.\(-2\)
              D.\(2\)
            • 9. 已知复数z满足(3+4i)z=25,则z=(  )
              A.3-4i
              B.3+4i
              C.-3-4i
              D.-3+4i
            • 10. 设,\(b\)为实,若复数\( \dfrac {12i}{+bi}=+i\)则\(a-b=(\) \()\)
              A.\(-2\)
              B.\(-1\)
              C.\(1\)
              D.\(2\)
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