Implicit differentiation dy/dx=xy^2

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SUMMARY

The discussion centers on solving the differential equation dy/dx = xy^2 with the initial condition x=1 when y=1. The correct solution derived from the implicit differentiation process is y = -2/(x^2 - 3), corresponding to option (B). The user initially struggled with the integration steps but ultimately clarified the integration of y^-1. The final answer was confirmed as option B, which is critical for students preparing for the AP test.

PREREQUISITES
  • Understanding of implicit differentiation
  • Familiarity with differential equations
  • Knowledge of integration techniques
  • Basic algebraic manipulation skills
NEXT STEPS
  • Study implicit differentiation techniques in calculus
  • Learn about solving first-order differential equations
  • Practice integration of rational functions
  • Review algebraic manipulation for solving equations
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Students preparing for AP Calculus, particularly those focusing on differential equations and implicit differentiation techniques.

mandymanny
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Homework Statement


If dy/dx=xy^2 and x=1 when y=1, then y=

(A) x^2
(B) -2/(x^2 -3)
(C) x^2 + 3
(D) 2/(x^2 +1)
(E) (x^2 -3)/2


Homework Equations





The Attempt at a Solution



dy/dx=xy^2
dy=xy^2dx
dy/y^2=x dx
∫dy/y^2=∫x dx
-1/y = x^2/2 + C
y=-2/x^2 + C
1=-2/1^2 + C
C=3
y=-2/x^2 +3

but that's not the answer...

please help i have the AP test tomorrow.
thanks
much appreciated
 
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Watch the step between line 5 and 6. f(x) = x^-1 is not linear.
 
That's not really implicit differentiation -- it's a diff. eq.
 
yes?

when i integrate, it's y^-1/-1 right? not just y^-1
??
 
Nevermind I got it.
Answer is B :)
 

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