So, I can say therefore, b we can obtained by a multiplied by z a by a square, you see the
I mean now this is a important part, but see a this is proportional to amplitude square
wave amplitude square, this must be proportional to response amplitude square.
Therefore, I can say b is equal to a which is equal to proportional to z square, because
see this, if you write write that this a square into z a square by a square that becomes a z
proportional to z a square, see a is nothing, but a square. So, it becomes proportional to
that.