Why is the sum of squares of the unit vector equal to one Amount```` Let the unit vectors be j and I be Square of j + square of I = 1 reason!

A vector with a module length of 1 is called the unit vector ～
If a is a unit vector, then | a | = 1
a*a=|a|*|a|*cos0°=1*1*1=1
And a * a = (I, J) * (I, J) = I & sup2; + J & sup2;
So I & sup2; + J & sup2; = 1

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