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given
an = (n -1) / (n + 1)
thus
a1 = (1-1) / (1+1) = 0 / 2 = 0
a2 = (2 - 1) / ( 2+ 1) = 1 / 3
a3 = (3 - 1) / (3 + 1) = 2 / 4
a4 = ( 4-1) / ( 4+1) = 3 / 5
thus
a1 + a2 + a3 + a4 = 0 + (1/3) + ( 2/4) + (3/5)
= ( 20 + 15 + 12) / 60
= 47 / 60
n|n) where N-ata. Use the result of [a, at] For harmonic oscillator system, with NIn) to prove 2. atIn) n+n1) and aln) Vn|n-1) (10%)
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Evaluate the following: Given that X~ N(, 2), E(x- x_bar)2 = ? We were unable to transcribe this imageWe were unable to transcribe this image
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