Graph f(x)=(0.4)^x
Problem
Solution
Identify the type of function. This is an exponential function of the form
ƒ(x)=bx where the baseb=0.4 Since0<0.4<1 the function represents exponential decay.Determine the y-intercept. By substituting
x=0 we findƒ(0)=(0.4)0=1 The graph passes through(0,1) Calculate additional points to define the shape.
Forx=1 ƒ(1)=0.4
Forx=2 ƒ(2)=0.16
Forx=−1 ƒ*(−1)=(0.4)(−1)=1/0.4=2.5
Forx=−2 ƒ*(−2)=(0.4)(−2)=1/0.16=6.25 Identify the horizontal asymptote. As
x increases toward infinity,(0.4)x approaches0 Therefore, the horizontal asymptote is the x-axis,y=0 Sketch the curve. Draw a smooth curve that decreases from left to right, passing through the calculated points and approaching the x-axis as
x becomes large.
Final Answer
Want more problems? Check here!