Exponential functions, step by step
An exponential function grows by a factor, not by a step.
The question
Evaluate f(x) = 2 · 8^x at x = 3.
Evaluate f(x) = 2 · 8ˣ at x = 3
f(3) = 2 · 8³
8³=512
2 · 512=1024
- Substitute x = 3: f(3) = 2 · 8³.
- Do the power first: 8³ = 512.
- Then multiply by the coefficient: 2 · 512 = 1024.
How it works.
- 01
Substitute x = 3: f(3) = 2 · 8³.
- 02
Do the power first: 8³ = 512.
- 03
Then multiply by the coefficient: 2 · 512 = 1024.