Lincoln’s parents invested $5,000 in a college savings account when he was born. If the account has a growth rate of 12%, the situation can be modeled by the equation a(t)=5,000(1.12)^t , where a is the amount after t years. Which one of the following statements is true about the graph of the function? Option #1: As t increases, a increases slowly at first and then quickly. Option $2: As t increases, a increases quickly at first and then slowly. Option #3: As t increases, a decreases slowly at first and then quickly. Option #4: As t increases, a decreases quickly at first and then slowly. (1 point) Option # is the true statement.

1 answer

The function given is \( a(t) = 5000(1.12)^t \), which is an exponential growth function. In general, exponential functions of the form \( a(t) = a_0(1 + r)^t \) (where \( r > 0 \)) will show a characteristic behavior:

  • They increase slowly at first when \( t \) is small because the factor \( (1.12)^t \) is still relatively small.
  • As \( t \) increases, the exponential term grows rapidly, causing the overall function \( a(t) \) to increase more quickly.

Given these characteristics, the correct statement about the graph of the function is:

Option #1: As t increases, a increases slowly at first and then quickly.