由(7),(12),(19)式经简单计算即可得证的翻译：(7), (12), (19) by simple calculation to permit 什么意思？中文翻译英文，英文翻译中文，怎么说？

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(7), (12), (19) by simple calculation to permit

Then proves by (7),(12),(19) type after the simple computation

From ( 7) and ( 12) and ( 19) type via a simple calculation can be a card

(7), (12), (19) by simple calculation to permit