Question

Which function forms an arithmetic sequence when x = 1, 2, 3, ...?

f(x)=- x/3 +5

f(x)= - 2^x

f(x)= 2x^2

f(x)= - 3/x + 5

Answer 1

when we have power function or exponential, or then we have a/x, then functions are not going to give arithmetic sequence, because an arithmetic sequence it is really a linear function when x are natural numbers,

so we need to check only A
f(x)=- x/3 +5

x 1 2 3 4 5
y 14/3 13/3 12/3 11/3 10/3 arithmetic difference is -1/3

so the answer is A