Question

Which of the following is a function equivalent to f(x) = 5(1.9)^3x?

f(x) = 34.29^x
f(x) = 5(6.86x)
f(x) = 5(6.86)^x
f(x) = 328.51^x

Answer 1

1.9^3 = 6.86, so assuming it's 1.9^3 and not 1.9^(3x) then the answer is
f(x) = 5(6.86x)
Your question isn't 100% clear though.

Answer 2

f(x) = 5(6.86)^x

Explanation:

The function f(x) can be simplified according the the laws of mathematics. The expression is 5 multiplied by the 1.9^3x. You cannnot multiply 5 with 1.9 because 1.9 has a power of 3x. The 5 can only be multiply by the 1.9 if the 5 had a power of x or if 1.9 has a power of just 3. Therefore:

f(x) = 5×(1.9×1,9×1.9)^x = 5×(6.86)^x