## VCabral1134 one year ago Help me plz will fan and give medal! Write the explicit formula for the geometric sequence. Then find the fifth term in the sequence. a^1 = −3, a^2 = 15, a^3 = −75 a. an = −3 ⋅ (−5)n ; 9375 c. an = −3 ⋅ (5)n ; –1875 b. an = −5 ⋅ (−3)n − 1 ; –405 d. an = −3 ⋅ (−5)n − 1 ; –1875

1. Nnesha

$\huge\rm a_n = a_1 \times r^{n-1}$ equation to find nth term of geometric seq. where a_1 is first term r= ratio n= term that u need

2. VCabral1134

thank you

3. Nnesha

to find common ratio divide next term with the previous one $\large\rm r=\frac{ a_2 }{ a_1}~~or~~\frac{ a_3 }{ a_2}$

4. Nnesha

a_2 = 2nd term a_3 = 3rd term

5. VCabral1134

r=-5

6. VCabral1134

D @Nnesha

7. VCabral1134

Am I right??

8. Nnesha

let me check wait a sec

9. VCabral1134

ok

10. Nnesha

right

11. VCabral1134

Yay!!

12. Nnesha

yahoo!