Question

4+8+12+...+88 ; 4+8+12+....+100 ; 4+8+12+....+200 , dai factor comun 4 ? urgent va rog , dau coroana si puncte !!!

Answer 1

Răspuns:

Explicație pas cu pas:

4+8+12+...+88 = 4*(1 + 2 + 3 + ... + 22) = 4*22*(1 + 22)/2 = 4*22*23/2 = 1012

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4+8+12+....+100 = 4*(1 + 2 + 3 + ... + 25) = 4*25*(1 + 25)/2 = 4*25*26/2 = 1300

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4+8+12+....+200 = 4*(1 + 2 + 3 + ... + 50) = 4*50*(1 + 50)/2 = 4*50*51/2 = 5100