The solution of dy/dx – y tan x – y2 sec x = 0 is given bya)y–1 = sin...
Substituting in the given equation, we get
The solution of dy/dx – y tan x – y2 sec x = 0 is given bya)y–1 = sin...
To solve the given differential equation, we can use the method of separating variables.
Separating variables involves isolating the terms with y and x on opposite sides of the equation.
The given differential equation is:
dy/dx - y tan(x) - y^2 sec(x) = 0
To begin, let's rearrange the equation:
dy/dx = y tan(x) + y^2 sec(x)
Now, we can separate the variables by moving all the terms involving y to one side and all the terms involving x to the other side:
dy/(y tan(x) + y^2 sec(x)) = dx
Next, we can integrate both sides of the equation.
Integrating the left side:
∫(1/(y tan(x) + y^2 sec(x))) dy
To simplify the integration, we can factor out y from the denominator:
∫(1/y(tan(x) + y sec(x))) dy
Now, we can use partial fraction decomposition to rewrite the integrand.
1/(y(tan(x) + y sec(x))) = A/y + B/(tan(x) + y sec(x))
Multiplying through by the denominator, we get:
1 = A(tan(x) + y sec(x)) + By
Expanding and equating coefficients, we find:
A = 1
B = -1
So, the integrand becomes:
1/y - 1/(tan(x) + y sec(x))
Now, we can integrate both terms separately:
∫(1/y) dy - ∫(1/(tan(x) + y sec(x))) dy
The integral of 1/y with respect to y is ln|y|.
For the second integral, we can use a substitution:
Let u = tan(x) + y sec(x)
Then, du = sec^2(x) + y sec(x) tan(x) dx
Rearranging, we have:
du - sec^2(x) dx = y sec(x) tan(x) dx
du - sec^2(x) dx = y du
Substituting back into the integral:
- ∫(1/u) du
This becomes -ln|u|.
Therefore, the integral of the second term is -ln|tan(x) + y sec(x)|.
Putting it all together, the integrated equation is:
ln|y| - ln|tan(x) + y sec(x)| = C
where C is the constant of integration.
Now, we can simplify the equation using logarithmic properties:
ln|y/(tan(x) + y sec(x))| = C
Exponentiating both sides:
|y/(tan(x) + y sec(x))| = e^C
Since e^C is a positive constant, we can remove the absolute value signs:
y/(tan(x) + y sec(x)) = e^C
Multiplying both sides by (tan(x) + y sec(x)), we get:
y = e^C (tan(x) + y sec(x))
Expanding, we have:
y = e^C tan(x) + e^C y sec(x)
Now, we can solve for y:
y - e^C y sec(x) = e^C tan(x
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