The differential equation representing the family of circles touching ...
Equation of circles touching y axis is given by
( x - a
2) + y
2 = a
2 where a is parameter implies x
2 + y
2 - 2ax = 0
Differentiating w.r.t. x, we get
2x + 2yy' - 2a = 0
implies a = x + yy'
So, differential equation will be
x
2 +y
2- 2x(x + yy
1) = 0
implies
So, differential equation is non-linear and of first order
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The differential equation representing the family of circles touching ...
Differential equation representing the family of circles touching the y-axis at the origin is non-linear and of first order.
Explanation:
To find the differential equation representing the family of circles touching the y-axis at the origin, let's consider a generic circle with center (a, b) and radius r.
Equation of this circle can be written as:
(x - a)^2 + (y - b)^2 = r^2
Since the circle touches the y-axis at the origin, the center of the circle lies on the y-axis. Therefore, the x-coordinate of the center is 0.
Substituting x = 0 in the equation of the circle, we get:
(0 - a)^2 + (y - b)^2 = r^2
a^2 + (y - b)^2 = r^2
Since the circle touches the y-axis at the origin, the y-coordinate of the center is equal to the radius. Therefore, a = r.
Substituting a = r in the equation, we get:
r^2 + (y - b)^2 = r^2
(y - b)^2 = 0
Taking the square root of both sides, we get:
y - b = 0
y = b
So, the equation of the circle becomes:
x^2 + (y - b)^2 = b^2
Differentiating this equation with respect to x, we get:
2x + 2(y - b) * (dy/dx) = 0
Simplifying this equation, we get:
x + (y - b) * (dy/dx) = 0
This is a non-linear and first-order differential equation, which represents the family of circles touching the y-axis at the origin.
Therefore, the correct answer is option 'C' - Non-linear and of first order.