Which explicit formula is equivalent to a1 = 1, an= 4an-1?
A. an = 1(4)^n-1
B. an = 4(4)^n-1
C. an = 4(1)^n–1
D. an = 1 + (n - 1)4

A. an = 1(4)^n-1

Step-by-step explanation:

Geometric sequence:

In a geometric sequence, the quotient between consecutive terms is always the same, called common ratio, and the sequence is given by:

In which is the first term and q is the common ratio.

We are given the following sequence:

So

That is, the quotient between consecutive terms is 4, so .

The first term is already given, . So

And thus, the correct answer is given by option A.

option 2 is correct.

step-by-step explanation:

we are given two inequality equation

x+y> 5 and -3x+2y< -2

first we draw the graph of both function using t-table method

equation: x+y> 5

for x=0, y=5

for x=-5, y=0

table:

x   :   0     5

y   :   5     0

test point (0,0) , 0> 5

false

equation: -3x+2y< -2

for x=0, y=-1

for x=2, y=4

table:

x   :   0     2

y   : -1       4

test point (0,0) , 0< -2

true

now we draw the graph. see the attachment for graph.

common region would be solution set.

option 2 is correct.