Answer:
an = 1/4(8)^n-1
Step-by-step explanation:
Given the following in a geometric sequence, a2=2, a3=16, and a4=128.
nth term of a sequence = ar^n-1
a is the first term
r is the common ratio
r = a3/a2 = a4/a3
r = 16/2 = 128/16
r = 8
a2 = ar
2 = 8a
a = 2/8
a = 1/4
The nth term by substituting the parameters will be;
an = 1/4(8)^n-1
Answer:
1 : 4 : 9
Step-by-step explanation:
Given the ratio of diameters = a : b , then
ratio of areas = a² : b²
Here ratio of diameters = 1 : 2 : 3 , so
ratio of areas = 1² : 2² : 3² = 1 : 4 : 9
Those are alternate interior angles and are equal. B.5x=80 x=16.