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Teknisk Elasticitetslre Plfig. Arealet over parabelkurven er af trekant ABC en The area over the parabola is of triangle ABC Asger Ostenfeld Teknisk Elasticitetslre pl fig google id jMJAAAAIAAJ scanned by google Asger Ostenfeld PDoldauto File Teknisk Elasticitetslre djvu Asger Ostenfeld Parabolas