Advertisements
Advertisements
Question
Solve the differential equation:
dr = a r dθ − θ dr
Solution
dr = a r dθ − θ dr
∴ (1 + θ) dr = a r dθ
∴ `(dr)/r = a (dθ)/((1 + θ))`
Integrating on both sides, we get
`int (dr)/r = a int (dθ)/(1+θ)`
log | r | = a log | 1 + θ| + log | c |
∴ log | r | = log | c(1 + θ)a|
∴ r = c (1 + θ)a
APPEARS IN
RELATED QUESTIONS
Find the differential equation of all the parabolas with latus rectum '4a' and whose axes are parallel to x-axis.
Show that the function y = A cos x + B sin x is a solution of the differential equation \[\frac{d^2 y}{d x^2} + y = 0\]
The rate of increase in the number of bacteria in a certain bacteria culture is proportional to the number present. Given the number triples in 5 hrs, find how many bacteria will be present after 10 hours. Also find the time necessary for the number of bacteria to be 10 times the number of initial present.
In a simple circuit of resistance R, self inductance L and voltage E, the current `i` at any time `t` is given by L \[\frac{di}{dt}\]+ R i = E. If E is constant and initially no current passes through the circuit, prove that \[i = \frac{E}{R}\left\{ 1 - e^{- \left( R/L \right)t} \right\}.\]
Find the equation of the curve which passes through the point (3, −4) and has the slope \[\frac{2y}{x}\] at any point (x, y) on it.
The slope of a curve at each of its points is equal to the square of the abscissa of the point. Find the particular curve through the point (−1, 1).
The solution of the differential equation y1 y3 = y22 is
The differential equation \[x\frac{dy}{dx} - y = x^2\], has the general solution
Solve the following differential equation.
x2y dx − (x3 + y3 ) dy = 0
Solve the following differential equation.
`dy/dx + y = e ^-x`
`dy/dx = log x`
For the differential equation, find the particular solution
`("d"y)/("d"x)` = (4x +y + 1), when y = 1, x = 0