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.
I think we can use the identity sin x/2 = sqrt [(1 - cos x) /2]
cos x - sqrt3 sqrt ( 1 - cos x) /sqrt2 = 1
cos x - sqrt(3/2) sqrt(1 - cos x) = 1
sqrt(3/2)(sqrt(1 - cos x) = cos x - 1 Squaring both sides:-
1.5 ( 1 - cos x) = cos^2 x - 2 cos x + 1
cos^2 x - 0.5 cos x - 0.5 = 0
cos x = 1 , -0.5
giving x = 0 , 2pi, 2pi/3, 4pi/3 ( for 0 =< x <= 2pi)
because of thw square roots some of these solutions may be extraneous so we should plug these into the original equations to see if they fit.
The last 2 results dont fit so the answer is x = 0 , 2pi Answer
Answer:
60 ml of 40% saline and 90 ml of 15% saline
Step-by-step explanation:
We can call the amount of 40% solution x and the amount of 15% solution y.
x + y = 150 -- (1)
0.40x + 0.15y = 150 * 0.25 -- (2) --- 150 * 0.25 = 37.5
40x + 15y = 3750 (Multiply (2) by 100 to get rid of decimals)
15x + 15y = 2250 -- (3) (Multiply (1) by 15)
25x = 1500 (Subtract (3) from (1)
x = 60
y = 150 - 60 = 90
6 83/100 should be correct