Question

Aratati ca 1+1/2+1/2^2+1/2^3+1/2^4+1/2^5+1/2^6+1/2^7+1/2^8 <2

Answer 1

Răspuns:

1=1/2⁰

E o progresie geometrică cu q(ratia)=1/2

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-- 1;1/2;1/2²....1/2⁷;1/2⁸

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a1=1

a2=1/2¹

a9=1/2⁸

S9=a1+a2+....a9

Calculele sunt in fotografie!