Giúp em nhanh ạ a)x+200=1+3+5+7+…..+313 b)x+2500=2+4+6+….+320 c)x+10(mũ10)=9+99+999+…..+9999999999

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1. a)x+200=1+3+5+7+…..+313

   x+200=(313-1) ÷ 2+1

   x+200=(313+1) × 157 ÷ 2

   x+200=24649

   x=24649-200

   x=24449

   b)x+2500=2+4+6+….+320

   x+2500=(320-2) ÷ 2+1

   x+2500=(320+2) × 110 ÷ 2

   x+2500=17710

   x=15210

   c)$(x+10)^{10}$ =9+99+999+…..+9999999999

   $(x+10)^{10}$ =(10-1)($10^{2}$ -1)…($10^{10}$ )

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