Geometric Series

Question 1

The sum of the terms of a G.P. is called a

• Ageometric series
• Bharmonic series
• Carithmetic series
• Dgeometric mean

Question 2

The sum of the first n terms of a G.P. with first term a_1 and common ratio r (r not equal to 1) is S_n =

• Aa_1(1 + r^n)/(1 - r)
• Ba_1(1 - r^n)/(1 - r)
• Ca_1(r^n - 1)/(1 - r)
• Da_1 r^n/(1 - r)

Question 3

An equivalent form of the G.P. sum formula is S_n =

• Aa_1(1 - r^n)/(r - 1)
• Ba_1(r^n + 1)/(r - 1)
• Ca_1(r^n - 1)/(r - 1)
• Da_1 r^n/(r - 1)

Question 4

The form S_n = a_1(1 - r^n)/(1 - r) is convenient when

• A|r| > 1
• Br = 1
• Cr = 0
• D|r| < 1

Question 5

The form S_n = a_1(r^n - 1)/(r - 1) is convenient when

• A|r| < 1
• B|r| > 1
• Cr = 0
• Dr = 1/2