Answered

Sumali sa IDNStudy.com at makuha ang mabilis at kaugnay na mga sagot. Alamin ang mga detalyadong sagot mula sa mga bihasang miyembro ng aming komunidad na sumasaklaw sa iba't ibang paksa para sa lahat ng iyong pangangailangan.

Sum of a geometric sequence

Find the sum:
A geometric sequence has first 3 terms and last term 48. If each term is twice the previous term, find the number of terms and the sum of the geometric sequence

Sagot :

Rhyckayenidn
There are a total of 4 terms. Since each term is twice the previous term, let 1st term=( a), 2nd term= (a*2), 3rd term=(a*2^2), then last term =( a*2^3). Stated that the last term is equal to 48, you can get an equation [48=(a*2^3)] to find a. The answer is a=6. We substitute it to the equation of terms above to find the numbers. .........The numbers would be 6,12,24 and 48.........Next,the formula for the sum would be "Sn=(a(1-r^n)/(1-r)" since the common ratio ( r )=2 and the first term ( a ) =6, we substitute it to the formula then we will get the sum (Sn)=90
Pinahahalagahan namin ang bawat tanong at sagot na iyong ibinabahagi. Huwag kalimutang bumalik at magtanong ng mga bagong bagay. Ang iyong kaalaman ay mahalaga sa ating komunidad. Salamat sa pagpili sa IDNStudy.com. Umaasa kami na makita ka ulit para sa mas maraming solusyon.