แบบทดสอบเก็บคะแนนเรื่องอนุกรมเลขคณิตและอนุกรมเรขาคณิต

1.จงหาผลบวกของ 25  พจน์แรกของอนุกรมเลขคณิต 2+8+14+20+...

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2.จงหาค่าของ  1+4+7+10+...+151

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3.จงหาผลบวกของจำนวนเต็มที่มีหลักหน่วยเป็น 1 ที่อยู่ระหว่าง 50 และ 350

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4.จงหาผลบวกของจำนวนคี่ตั้งแต่ 17 ถึง 379

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5. กำหนดให้ 1,2,5,6,9,10,13,14,17,18,21,22,… เป็นอนุกรม ถ้า  เป็นผลบวก n พจน์แรกของอนุกรมดังกล่าวจงหา  มีค่าเท่าใด

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6.กำหนดให้ A={97,98,99,100,101,…,1025}  ถ้า x เป็นผลบวกของจำนวนคี่ใน A   และ y เป็นผลบวกของจำนวนคู่ใน A    จงหาค่าของ x-y

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7.จงหาผลบวกของ 8 พจน์แรกของอนุกรมเรขาคณิต   1+2+4+8+…

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8.จงผลบวกของอนุกรมเรขาคณิต 1-3+9-27+...-2187

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9. อนุกรมเรขาคณิตมีพจน์แรกเป็น 160 และอัตราส่วนร่วมเป็น  ถ้าผลบวก  n  พจน์แรกเป็น 2,110  แล้วจงหาค่าของ n

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