Question immanu

2.1 Nonlinear Functions - Function composition and evaluation
0:00

Immanuel purchased a certain rare coin on January 1. The function f(x)=651.03x, where 0x10, gives the predicted value, in dollars, of the rare coin x years after Immanuel purchased it. What is the best interpretation of the statement “f8 is approximately equal to 82 ” in this context?

A.

When the rare coin's predicted value is approximately 82 dollars, it is 8 % greater than the predicted value, in dollars, on January 1 of the previous year.

B.

When the rare coin’s predicted value is approximately 82 dollars, it is 8 times the predicted value, in dollars, on January 1 of the previous year.

C.

From the day Immanuel purchased the rare coin to 8 years after Immanuel purchased the coin, its predicted value increased by a total of approximately 82 dollars.

D.

8 years after Immanuel purchased the rare coin, its predicted value is approximately 82 dollars.

Immanuel purchased a certain rare coin on January 1. The function f ( x ) =

Hard-difficulty · SAT Math · Nonlinear Functions — Function composition and evaluation. Read the question above, select your answer, and check the full explanation below to understand exactly why the correct choice works.

Answer explanation

Choice D is correct. It’s given that the function fx=651.03x gives the predicted value, in dollars, of a certain rare coin x years after Immanuel purchased it. It follows that fx represents the predicted value, in dollars, of the coin x years after Immanuel purchased it. Since the value of f8 is the value of fx when x = 8 , it follows that “f8 is approximately equal to 82 ” means that fx is approximately equal to 82 when x = 8 . Therefore, the best interpretation of the statement “f8 is approximately equal to 82 ” in this context is 8 years after Immanuel purchased the rare coin, its predicted value is approximately 82 dollars.

Choice A is incorrect and may result from conceptual errors.

Choice B is incorrect and may result from conceptual errors.

Choice C is incorrect and may result from conceptual errors.