Advanced MathEasyEvaluating an exponential function
Advanced Math practice question
The function f is defined by f(x) = 3 · 2ˣ. What is the value of f(4)?
Answer: 48
f(4) = 3 · 2⁴ = 3 · 16 = 48. The exponent applies to the 2 only, not to the 3.
Common wrong answers
- If you answered 11
- 11 is 3 + 8. The function multiplies 3 by 2ˣ; it doesn't add.
- If you answered 24
- 24 is 3 · 8 = 3 · 2³. The input is 4, so 2⁴ = 16.
- If you answered 1296
- 1,296 is 6⁴ — the 3 and 2 were multiplied BEFORE raising to the power. Only the 2 is raised: 3 · 16.
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