Question

Which of the following is an exponential function?

Select one:
A. f(x)=2.79^x−13.6
B. f(x)=x(0.4)^19+7
C. f(x)=−9x^6+5.44x
D. f(x)=−49(x)^x+3

Answer 1

I am not sure but it can be B

Answer 2

The answer is B
F(x)=x(0.4)^19+7