Question

Help!!!!!!!!!Dau multe puncte si funda!!!!!!

Daca x ∈ N si 1+3+5+...+(2x-1)=100,atunci x este......

Answer 1

1 + 3 + 5 + ... + (2x - 1) = 100

1 + 3 + 5 + ... + (2x - 1) = x^2

x^2 = 100

x^2 = 10^2

x = 10
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Verificare:

1 + 3 + 5 + ... + (2 × 10 - 1) =

1 + 3 + 5 + ... + 19 =

(1 + 19) + (3 + 17) + (5 + 15) + (7 + 13) + (9 + 11) =

20 × 5 =

100