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Mathematics Question on Differential equations

If the solution curve of the differential equation dydx=x+y2xy\frac{dy}{dx} = \frac{x + y - 2}{x - y} passing through the point (2,1)(2, 1) is tan1(y1x1)1βloge(α+(y1x1)2)=logex1,\tan^{-1}\left(\frac{y - 1}{x - 1}\right) - \frac{1}{\beta} \log_e\left(\alpha + \left(\frac{y - 1}{x - 1}\right)^2\right) = \log_e |x - 1|, then 5β+α5\beta + \alpha is equal to

Answer

Given:
dydx=x+y2xy.\frac{dy}{dx} = \frac{x + y - 2}{x - y}.

Substitute:
x=X+h,y=Y+k.x = X + h, \quad y = Y + k.

Let:
h+k=2,hk=0    h=k=1.h + k = 2, \quad h - k = 0 \implies h = k = 1.

So:
Y=vX,dvdX=1+v21v.Y = vX, \quad \frac{dv}{dX} = \frac{1 + v^2}{1 - v}.

Integrating and applying the condition (2, 1):
tan1(y1x1)=12loge(1+(y1x1)2)logex1.\tan^{-1} \left(\frac{y - 1}{x - 1}\right) = \frac{1}{2} \log_e \left(1 + \left(\frac{y - 1}{x - 1}\right)^2\right) - \log_e |x - 1|.

From the equation:
α=1,β=2.\alpha = 1, \quad \beta = 2.

Calculating 5β+α5\beta + \alpha:
5β+α=5×2+1=11.5\beta + \alpha = 5 \times 2 + 1 = 11.

Thus, the Correct Answer is 11.

Let me know if further clarification is needed!
The Correct answer is: 11