一道复数题,求证证明│z1w1+z2w2│²≤(│z1│²+│z2│²)(│w1│²+│w2│²)

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一道复数题,求证证明│z1w1+z2w2│²≤(│z1│²+│z2│²)(│w1│²+│w2│²)

一道复数题,求证证明│z1w1+z2w2│²≤(│z1│²+│z2│²)(│w1│²+│w2│²)
一道复数题,求证
证明│z1w1+z2w2│²≤(│z1│²+│z2│²)(│w1│²+│w2│²)

一道复数题,求证证明│z1w1+z2w2│²≤(│z1│²+│z2│²)(│w1│²+│w2│²)
我用大写表示共轭
左边=(z1w1+z2w2)(Z1W1+Z2W2)
=|z1w1|^2+|z2w2|^2+z1w1Z2W2+Z1W1z2w2
因为|z1W2-z2W1|^2=|z1W2|2+|z2W1|^2-z1W2Z2w1-Z1w2z2W1>=0
因此z1w1Z2W2+Z1W1z2w2