#Direct sum

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sudden karma
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In Linear Algebra Done Right, by Sheldon Axler, the proposition 1.45 states "(V_1 + \cdots + V_m) is a direct sum if and only if the only way to write 0 as a sum (v_1 + \cdots + v_m), where each (v_k \in V_k) is by taking each (v_k) equal to 0". However, why can't I take (v_1 = -v_2)? My idea is to write something like "(0 = (-5) + 5 + 0 + \cdots + 0)" but using vectors.

stiff latchBOT
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dense portal
sudden karma
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Oh

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Got it

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Thank you!

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+close

molten narwhalBOT
# sudden karma +close
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