<item ident="F4-5213" title="F4 | Implicit solutions for exact IVPs | ver. 5213">
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<div class="exercise-statement">
<p>
<strong>F4.</strong>
</p>
<p> Determine which of the following ODEs is exact. </p>
<p style="text-align:center;">
<img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?6 \, t y^{2} + 6 \, t = 2 \, t^{2} {y'} - 2 \, t y {y'} - 2 \, t {y'}" alt="6 \, t y^{2} + 6 \, t = 2 \, t^{2} {y'} - 2 \, t y {y'} - 2 \, t {y'}" title="6 \, t y^{2} + 6 \, t = 2 \, t^{2} {y'} - 2 \, t y {y'} - 2 \, t {y'}" data-latex="6 \, t y^{2} + 6 \, t = 2 \, t^{2} {y'} - 2 \, t y {y'} - 2 \, t {y'}"/>
</p>
<p style="text-align:center;">
<img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y" alt="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y" title="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y" data-latex="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y"/>
</p>
<p> Then find an implicit solution for this exact ODE satisfying the initial value <img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?y( 1 )= -1" alt="y( 1 )= -1" title="y( 1 )= -1" data-latex="y( 1 )= -1"/>. </p>
</div>
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<mattext texttype="text/html"><div class="exercise-statement">
<p>
<strong>F4.</strong>
</p>
<p> Determine which of the following ODEs is exact. </p>
<p style="text-align:center;">
<img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?6%20%5C,%20t%20y%5E%7B2%7D%20+%206%20%5C,%20t%20=%202%20%5C,%20t%5E%7B2%7D%20%7By'%7D%20-%202%20%5C,%20t%20y%20%7By'%7D%20-%202%20%5C,%20t%20%7By'%7D" alt="6 \, t y^{2} + 6 \, t = 2 \, t^{2} {y'} - 2 \, t y {y'} - 2 \, t {y'}" title="6 \, t y^{2} + 6 \, t = 2 \, t^{2} {y'} - 2 \, t y {y'} - 2 \, t {y'}" data-latex="6 \, t y^{2} + 6 \, t = 2 \, t^{2} {y'} - 2 \, t y {y'} - 2 \, t {y'}">
</p>
<p style="text-align:center;">
<img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?-6%20%5C,%20t%20y%5E%7B2%7D%20-%206%20%5C,%20t%20=%206%20%5C,%20t%5E%7B2%7D%20y%20%7By'%7D%20+%202%20%5C,%20t%20%7By'%7D%20+%202%20%5C,%20y" alt="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y" title="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y" data-latex="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y">
</p>
<p> Then find an implicit solution for this exact ODE satisfying the initial value <img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?y(%201%20)=%20-1" alt="y( 1 )= -1" title="y( 1 )= -1" data-latex="y( 1 )= -1">. </p>
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<response_label ident="answer1" rshuffle="No"/>
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<div class="exercise-answer">
<h4>Partial Answer:</h4>
<p>The following ODE is exact.</p>
<p style="text-align:center;">
<img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y" alt="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y" title="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y" data-latex="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y"/>
</p>
<p> Its implicit solution satisfying the initial value is: </p>
<p style="text-align:center;">
<img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?-3 \, t^{2} y^{2} - 3 \, t^{2} - 2 \, t y = \left(-4\right)" alt="-3 \, t^{2} y^{2} - 3 \, t^{2} - 2 \, t y = \left(-4\right)" title="-3 \, t^{2} y^{2} - 3 \, t^{2} - 2 \, t y = \left(-4\right)" data-latex="-3 \, t^{2} y^{2} - 3 \, t^{2} - 2 \, t y = \left(-4\right)"/>
</p>
</div>
</mattextxml>
<mattext texttype="text/html"><div class="exercise-answer">
<h4>Partial Answer:</h4>
<p>The following ODE is exact.</p>
<p style="text-align:center;">
<img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?-6%20%5C,%20t%20y%5E%7B2%7D%20-%206%20%5C,%20t%20=%206%20%5C,%20t%5E%7B2%7D%20y%20%7By'%7D%20+%202%20%5C,%20t%20%7By'%7D%20+%202%20%5C,%20y" alt="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y" title="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y" data-latex="-6 \, t y^{2} - 6 \, t = 6 \, t^{2} y {y'} + 2 \, t {y'} + 2 \, y">
</p>
<p> Its implicit solution satisfying the initial value is: </p>
<p style="text-align:center;">
<img style="border:1px #ddd solid;padding:5px;border-radius:5px;" src="https://latex.codecogs.com/svg.latex?-3%20%5C,%20t%5E%7B2%7D%20y%5E%7B2%7D%20-%203%20%5C,%20t%5E%7B2%7D%20-%202%20%5C,%20t%20y%20=%20%5Cleft(-4%5Cright)" alt="-3 \, t^{2} y^{2} - 3 \, t^{2} - 2 \, t y = \left(-4\right)" title="-3 \, t^{2} y^{2} - 3 \, t^{2} - 2 \, t y = \left(-4\right)" data-latex="-3 \, t^{2} y^{2} - 3 \, t^{2} - 2 \, t y = \left(-4\right)">
</p>
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