Question

Find the equation of the exponential function represented by the table below:

Answer 1

y = 0.2(0.5)^x

Explanation:

Exponential function are of the form

y = ab^x

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To find "a" plug in x = 0 y = 0.2

0.2 = a(0.2)^0

0.2 = a

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To find "b" plug in another point and a = 0.2

using x = 2, b = 0.05

0.05 = 0.2b^2

Divide both sides by 0.20

.25 = b^2

Take the square root of both sides

0.5 = b

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With a = 0.2 and b = 0.5 the equation becomes

y = 0.2(0.5)^x