Question

Which is the graph of the sequence def by the function f(x) = 100(0.5)x - 1?

On a coordinate plane, 4 points are plotted. The points are (0, 100), (1, 50), (2, 25), (3, 12.5).

On a coordinate plane, 4 points are plotted. The points are (1, 100), (2, 50), (3, 25), (4, 12.5).

On a coordinate plane, 3 points are plotted. The points are (0, 100), (2, 90), (4, 80).

On a coordinate plane, 3 points are plotted. The points are (1, 100), (3, 90), (5, 80).ined

Answer 1

Assuming the intended function is f(x) = 100(0.5)^x, evaluate at integer x:

f(0) = 100(0.5)^0 = 100
f(1) = 100(0.5)^1 = 50
f(2) = 100(0.5)^2 = 25
f(3) = 100(0.5)^3 = 12.5

So the correct graph is the first one: (0, 100), (1, 50), (2, 25), (3, 12.5).

(If the sequence were indexed starting at 1, i.e. f(n)=100(0.5)^{n-1}, the second option would be used.)