Question

4) Simplificati 3+ 6+12+...+ 6042/ 5+10+15+...+10070 = ​

Answer 1

Răspuns:

2+4+6+...+140<=>2(1+2+3+...+70)

3+6+9+210<=>3(1+2+3+...+70)

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+

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+

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+

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+

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)

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2

3

3(1+2+3+...+70)

2(1+2+3+...+70)

unde Sumele Gauss se simplifica

prin Suma Gauss si ramane:

3

2