7cos(x) + 1 = 6sec(x)
7cos(x) + 1 = 6/cos(x)
7cos^(x) + cos(x) = 6
7cos^(x) + cos(x) - 6 = 0
[7cos(x) - 6][cos(x) + 1] = 0
cos(x) = 6/7 , x = arccos(6/7) and
cos(x) = -1, x = 180
Answer:
5.93 years
Step-by-step explanation:
The continuous compounding formula tells you the amount after t years will be ...
A = Pe^(rt) . . . . principal P compounded continuously at annual rate r for t years
7400 = 5500e^(0.05t)
ln(7400/5500) = 0.05t . . . . divide by 5500, take natural logs
t = 20×ln(74/55) ≈ 5.93
It will take about 5.93 years for $5500 to grow to $7400.
$125 per quarter, if quarter means every 3 months.
