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Grade 12Algebra

If (z1 -2z2 /2-z1 z2 ) is unimodulus and z2 is not unimodulus then find | z1 |?

Profile image of harendar singh
16 Years agoGrade 12
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3 Answers

Profile image of Jitender Singh
11 Years ago
Ans:
Hello Student,
Please find answer to your question below

Given:
|\frac{z_{1}-2z_{2}}{1-2z_{1}z_{2}}| = 1
|z_{1}-2z_{2}| =|1-2z_{1}z_{2}|
|z_{1}-2z_{2}|^{2} =|1-2z_{1}z_{2}|^{2}
|z_{1}|^{2}+4|z_{2}|^{2}-4|z_{1}||z_{2}| = 1 + 4|z_{1}|^{2}|z_{2}|^{2} - 4|z_{1}||z_{2}|
|z_{1}|^{2}+4|z_{2}|^{2} = 1 + 4|z_{1}|^{2}|z_{2}|^{2}
|z_{1}|^{2}(1-4|z_{2}|^{2}) = 1-4|z_{2}|^{2}
|z_{1}|^{2} = 1
|z_{1}| = 1


Profile image of mycroft holmes
11 Years ago
Testing Latex 
Profile image of mycroft holmes
11 Years ago
By the way you cannot expand the modulus squared the way you have done. Please revise your answer