I have the linear mapping Pw(x).(adsbygoogle = window.adsbygoogle || []).push({});

How can I prove that:

[itex]||P_w(x)||^2 = \Sigma (<x, x_i>)^2[/itex]

Where the sum is from i = 1 to k

x is any vector which is an element of [itex]R^n[/itex]

I have tried expanding [itex]||P_w(x)||^2[/itex] but it doesn't seem to give me the right side of the equation.

Is there any other method you can suggest?

Thank you.

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# Homework Help: LINEAR ALGEBRA: Linear Mapping

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