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Algebra Difficulty 2.9 Junior Find the answer

Given that the complex number zz satisfies (1+i)z=2i(1+i)z=2i (ii is the imaginary unit), find the conjugate of zz, denoted as zˉ\bar{z} = \underline{\quad\quad} .

A number or a short expression. Spacing and $ signs are ignored.

Solution

Since (1+i)z=2i(1+i)z=2i,

We have z=2i1+i=2i(1i)(1+i)(1i)=2+2i2=1+iz= \frac {2i}{1+i} = \frac {2i(1-i)}{(1+i)(1-i)} = \frac {2+2i}{2} = 1+i,

Hence, the conjugate of zz is zˉ=1i\bar{z} = 1-i.

So the answer is: zˉ=1i\boxed{\bar{z} = 1-i}.

This is obtained by manipulating the original equation and using the algebraic form of complex numbers to simplify the value. This question tests the understanding of multiplication and division operations with complex numbers in algebraic form, which is a basic concept.

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.