If the first term, common ratio and the last term of a G.P. are a, r and l respectively, then the nth term from the end of the G.P. is given by :

1. lr^{n - 1}

2. lr^{1 - n}

3. $\dfrac{l}{r^{1 - n}}$

4. $\dfrac{l}{r^{n + 1}}$

The product of n terms of a G.P. with first term a and common ratio r, when r = 1, is :

1. $\dfrac{a(r^n-1)}{r-1}$

2. na

3. arⁿ

4. aⁿ

The sum of n terms of a G.P. with first term a and common ratio r, when r > 1, is :

1. $\dfrac{ar^n-1}{r-1}$

2. $\dfrac{1-ar^n}{1-r}$

3. $\dfrac{a(r^n-1)}{r-1}$

4. $\dfrac{a(1-r^n)}{1-r}$

The sum of n terms of a G.P. with first term a and common ratio r, when r < 1, is :

1. $\dfrac{ar^n-1}{r-1}$

2. $\dfrac{1-ar^n}{1-r}$

3. $\dfrac{a(r^n-1)}{r-1}$

4. $\dfrac{a(1-r^n)}{1-r}$