Recall that variation of parameters is used to solve second-order ODEs of the form
<em>y''(t)</em> + <em>p(t)</em> <em>y'(t)</em> + <em>q(t)</em> <em>y(t)</em> = <em>f(t)</em>
so the first thing you need to do is divide both sides of your equation by <em>t</em> :
<em>y''</em> + (2<em>t</em> - 1)/<em>t</em> <em>y'</em> - 2/<em>t</em> <em>y</em> = 7<em>t</em>
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You're looking for a solution of the form

where


and <em>W</em> denotes the Wronskian determinant.
Compute the Wronskian:

Then


The general solution to the ODE is

which simplifies somewhat to

Answer:
Step-by-step explanation:
The above is a right angled triangle
So you take the longest side
9.4^2 - 6.8^2
88.36- 46.24
sqrt of 42.12
6.4899
To the nearest tenth of a degree = 6.56.5ft
Answer:
Step-by-step explanation:
Since we have an amount in the future of 750, we are going to use Future value formula; FV = PV (1+r)^t
where PV= Initial amount deposited
r= interest rate or discount rate
t = total duration of the investment
FV= 750
PV=500
r = 2.5% or 0.025 as a decimal
t = ?
Next, plug in the numbers into the formula;
750 = 500* (1+0.025)^t
divide both sides by 500;
750/500 = 1.025^t
Introduce <em>ln</em> on both sides
ln 1.5 = ln 
ln 1.5 = t ln 1.025
0.4054651 = 0.0246926 t
Divide both sides by 0.0246926 to solve for t;
0.4054651/0.0246926 = t
t = 16.42
Therefore it will take 16.42 years
Like you would put 0.5 or 1. or 1.5 as like 1/2 or 1/3 and you plot negatives first