#### Question

If f(x+y) = f(x)f(y) such that f(3) = 64. Find the value of f(2)-f(1) .

Question

If f(x+y) = f(x)f(y) such that f(3) = 64. Find the value of f(2)-f(1) .

f(x+y) = f(x)f(y) implies f(x) is an exponential function a^x.

f(3) = 64 = 4^3 suggests f(x) = 4^x

Therefore

f(2)-f(1) = 4^2-4^1 = 12