Question
Solve the following differential equations:$\text{y}(1+\text{e}^{\text{x}})\text{dy}=(\text{y}+1)\text{e}^{\text{x}}\text{ dx}$

Answer

We have,
$\text{y}(1+\text{e}^{\text{x}})\text{dy}=(\text{y}+1)\text{e}^{\text{x}}\text{ dx}$
$\Rightarrow\frac{\text{y}}{\text{y}+1}\text{dy}=\frac{\text{e}^{\text{x}}}{1+\text{e}^{\text{x}}}\text{dx}$
Integrating both sides, we get
$\int\frac{\text{y}}{\text{y}+1}\text{dy}=\int\frac{\text{e}^{\text{x}}}{1+\text{e}^{\text{x}}}\text{dx}$
Substituting $1+\text{e}^{\text{x}}=\text{t},$ we get
$\text{e}^{\text{x}}\text{dx = dt}$
$\therefore\int\frac{\text{y}}{\text{y}+1}\text{dy}=\int\frac{1}{\text{t}}\text{dt}$
$\Rightarrow\int\frac{\text{y}+1-1}{\text{y}+1}\text{dy}=\int\frac{1}{\text{t}}\text{dt}$
$\Rightarrow\int\text{dy}-\int\frac{1}{\text{y}+1}\text{dy}=\int\frac{1}{\text{t}}\text{dt}$
$\Rightarrow\text{y}-\log|\text{y}+1|=\log|\text{t}|+\text{C}$
$\Rightarrow\text{y}-\log|\text{y}+1|=\log|1+\text{e}^{\text{x}}|+\text{C}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Solve the following determinant equations:
$\begin{vmatrix}3&-2&\sin(3\theta)\\-7&8&\cos(2\theta)\\-11&14&2\end{vmatrix}=0$
Evaluate the following integrals:$\int\limits^{\pi}_0\frac{\text{x}\sin\text{x}}{1+\sin\text{x}}\text{ dx}$
A class has 15 students whose ages are 14, 17, 15, 14, 21, 17, 19, 20, 16, 18, 20, 17, 16, 19 and 20 years. One student is selected in such a manner that each has the same chance of being chosen and the age X of the student is recorded. What is the probability distribution of the random variable X? Find mean, variance, and standard deviation of X.
A school wants to award its students for the values of Honesty, Regularity and Hard work with a total cash award of Rs. 6,000. Three times the award money for Hard work added to that given for honesty amounts to Rs. 11,000. The award money given for Honesty and Hard work together is double the one given for Regularity. Represent the above situation algebraically and find the award money for each value, using matrix method. Apart from these values, namely, Honesty, Regularity and Hard work, suggest one more value which the school must include for awards.
Differentiate the following functions with respect to x:
$\tan^{-1}\Big(\frac{4\text{x}}{1-4\text{x}^2}\Big),-\frac{1}{2}<\text{x}<\frac{1}{2}$
Solve the following differential equations:$\cos\text{x}\cos\text{y}\frac{\text{dy}}{\text{dx}}=-\sin\text{x}\sin\text{y}$
A rectangular sheet of tin $45\ cm$ by $24\ cm$ is to be made into a box without top, in cutting off squares from each corners and folding up the flaps. What should be the side of the square to be cut off so that the volume of the box is maximum possible?
Evaluate the following integrals:
$\int\tan^5\text{x}\text{ dx}$
Show that the following curves intersect orthogonally at the indicated points:
$y^2 = 8x $and $2x^2 + y^2 = 10 $at $\big(1,2\sqrt{2})$
Evaluate the following integrals:
$\int\text{e}^{2\text{x}}\sin(3\text{x}+1)\text{dx}$