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Find the equilibrium solutions of the differential equation specified

1.dy/dt=y+3/1-y 2. dy/dt=(t^2-1)(y^2-2)/y^2-4

1 Answer

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Answer:

(t, y) = (1, 2), (1, -2), (-1, 2), and (-1, -2).

Explanation:

Let's solve each differential equation and find their equilibrium solutions.

dy/dt = y + 3 / (1 - y)

To find the equilibrium solutions, we set dy/dt equal to zero:

0 = y + 3 / (1 - y)

Now, we can solve for y:

y(1 - y) = -3

y - y^2 = -3

y^2 - y + 3 = 0

This is a quadratic equation. We can apply the quadratic formula:

y = (-(-1) ± √((-1)^2 - 4(1)(3))) / (2(1))

Simplifying further:

y = (1 ± √(1 - 12)) / 2

y = (1 ± √(-11)) / 2

Since the discriminant is negative, there are no real solutions for y. Therefore, this differential equation does not have any equilibrium solutions.

dy/dt = (t^2 - 1)(y^2 - 2) / (y^2 - 4)

Setting dy/dt to zero:

0 = (t^2 - 1)(y^2 - 2) / (y^2 - 4)

This equation is satisfied when either the numerator is zero or when the denominator is zero.

Numerator: t^2 - 1 = 0

This gives two solutions: t = 1 and t = -1.

Denominator: y^2 - 4 = 0

This gives two solutions: y = 2 and y = -2.

Therefore, the equilibrium solutions for this differential equation are:

(t, y) = (1, 2), (1, -2), (-1, 2), and (-1, -2).

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