Equations involving argument and conjugate of a complex numbers

If z=\[\frac{a+ib}{c+id}\]

then after rationalizing we get =\[\frac{(a+ib)(c-id)}{(c+id)(c-id)}\]=\[\frac{ac+bd+i(bc-ad)}{(c^2+d^2)}\]

The conjugate of a complex number z=a+ib is denoted by \[\bar{z}\]and is defined as  \[\bar{z}=a-ib\].

Case1 if Z= 2+3i then  \[\bar{z}=2-3i\].

Case 2 If \[z_1=a+ib\] and \[z_2=c-id \]

           then conjugate of \[z_1+z_2\]=conjugate of \[z_1\]+conjugate of \[z_2\] ..............................property -1

For Example  \[z_1=5+6i\] and \[z_2=3-8i \] then  conjugate of \[z_1+z_2\]=8+2i

 Case 3  If \[z_1=a+ib\] and \[z_2=a-ib \]

           then conjugate of \[z_1+z_2\]=conjugate of \[z_1\]+conjugate of \[z_2\]=\[2a\]....................special case

Note - \[z_1\] and \[z_2\] are cojugate of each other

Case 4. If imaginary part of complex number is zero then conjugate of the complex number is number itself.

             Example z=2 then \[\bar{z}\]=2

Case 5. When real part of complex number is zero.

          Example z=2i then \[\bar{z}\]=-2i

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