the value of a savings account after t years is given by: v(t)=131(1.15^t) thousand dollars. calculator…

the value of a savings account after t years is given by: v(t)=131(1.15^t) thousand dollars. calculator checkpoint: v(2)=173.2475 a. calculate the value of the savings account after 8 years. (round your answer to three decimal places.) b. calculate the rate of change of the savings account after 8 years. (round your answer to three decimal places.) thousand dollars per year c. write the linearization of v after 8 years. (round all numerical values to three decimal places.) v_l(t)= thousand dollars d. use the linearization in part (c) to estimate the value of the savings account after 8.1 years. (round your answer to three decimal places.) thousand
Answer
Explanation:
Step1: Find value at (t = 8)
Substitute (t = 8) into (V(t)=131(1.15^{t})). [V(8)=131\times1.15^{8}] [V(8)=131\times3.05902286] [V(8)\approx 400.732]
Step2: Find derivative of (V(t))
The derivative of (y = a\cdot b^{t}) is (y^\prime=a\cdot b^{t}\ln(b)). For (V(t)=131(1.15^{t})), (V^\prime(t)=131\times1.15^{t}\ln(1.15)). Substitute (t = 8) into (V^\prime(t)): [V^\prime(8)=131\times1.15^{8}\ln(1.15)] [V^\prime(8)=131\times3.05902286\times0.13976194] [V^\prime(8)\approx 55.903]
Step3: Find linear - ization
The linearization of a function (y = V(t)) at (t = a) is given by (V_{L}(t)=V(a)+V^\prime(a)(t - a)). Here (a = 8), (V(8)\approx400.732) and (V^\prime(8)\approx55.903). [V_{L}(t)=400.732+55.903(t - 8)] [V_{L}(t)=400.732+55.903t-447.224] [V_{L}(t)=55.903t - 46.492]
Step4: Estimate value at (t = 8.1)
Substitute (t = 8.1) into (V_{L}(t)): [V_{L}(8.1)=55.903\times8.1-46.492] [V_{L}(8.1)=452.8143 - 46.492] [V_{L}(8.1)\approx406.322]
Answer:
a. (400.732) b. (55.903) c. (V_{L}(t)=55.903t - 46.492) d. (406.322)