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NO LINKS!!! URGENT HELP PLEASE!!!
Please help with #2 and 4

NO LINKS!!! URGENT HELP PLEASE!!! Please help with #2 and 4-example-1
User Hexana
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1 Answer

1 vote

Answer:


\textsf{2)} \quad f(x)=5 (2)^x


\textsf{3)} \quad f(x)=4 \left((1)/(2)\right)^x

Explanation:

Exponential Function

The general formula for an exponential function is:


\boxed{f(x)=ab^x}

where:

  • a is the initial value (y-intercept).
  • b is the base (growth/decay factor) in decimal form.

Question 2

From inspection of the graph, this is a exponential growth function.

The end behaviours of the function are:

  • As x → -∞, f(x) → 0
  • As x → +∞, f(x) → +∞

The y-intercept is (0, 5), so a = 5.

Another point on the curve is (1, 10).

Substitute a = 5 and point (1, 10) into the formula and solve for b:


\implies y=ab^x


\implies 10=5 \cdot b^1


\implies 10=5 \cdot b


\implies b =2

Therefore, the equation of the exponential function is:


f(x)=5 (2)^x

Question 4

From inspection of the graph, this is a exponential decay function.

The end behaviours of the function are:

  • As x → -∞, f(x) → +∞
  • As x → +∞, f(x) → 0

The y-intercept is (0, 4), so a = 4.

Another point on the curve is (2, 1).

Substitute a = 4 and point (2, 1) into the formula and solve for b:


\implies y=ab^x


\implies 1=4 \cdot b^(2)


\implies b^2= (1)/(4)


\implies b= (1)/(2)

Therefore, the equation of the exponential function is:


f(x)=4 \left((1)/(2)\right)^x

User Exacerbatedexpert
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