Advertisements
Advertisements
प्रश्न
Solve the following:
`("d"y)/("d"x) + y tan x = cos^3x`
उत्तर
It is of the form `("d"y)/("d"x) + "P"y` = Q
Here P = tan x
Q = cos3x
`int "Pd"x = int tan x "d"x`
= `int sinx/cosx "d"x`
= `- int (- sinx)/cosx "d"x`
= – log cos x
= log sec x
I.F = `"e"^(int Pdx)`
= `"e"^(log sec x)`
= sec x
The required solution is
y(I.F) = `int "Q" ("I.F") "d"x + "c"`
y(sec x) = `int cos^3x (sec x) "d"x + "c"`
y(sec x) = `int cos^3x 1/cosx "d"x + "c"`
y(sec x) = `int cos^2x "d"x + "c"`
y(sec x) = `int ((1 + cos 2x)/2) "d"x + "c"`
y(sec x) = `1/2 int (1 + cos2x) "d"x + "c"`
y(sec x) = `1/2 [x + (sin2x)/2] + "c"`
APPEARS IN
संबंधित प्रश्न
If F is the constant force generated by the motor of an automobile of mass M, its velocity V is given by `"M""dv"/"dt"` = F – kV, where k is a constant. Express V in terms of t given that V = 0 when t = 0
The velocity v, of a parachute falling vertically satisfies the equation `"v" (dv)/(dx) = "g"(1 - v^2/k^2)` where g and k are constants. If v and are both initially zero, find v in terms of x
Solve the following differential equation:
`("d"y)/("d"x) = tan^2(x + y)`
Solve the following differential equation:
(x2 + y2) dy = xy dx. It is given that y (1) = y(x0) = e. Find the value of x0
Choose the correct alternative:
If sin x is the integrating factor of the linear differential equation `("d"y)/("d"x) + "P"y = "Q"`, then P is
Solve the following homogeneous differential equation:
An electric manufacturing company makes small household switches. The company estimates the marginal revenue function for these switches to be (x2 + y2) dy = xy dx where x represents the number of units (in thousands). What is the total revenue function?
Solve the following:
`("d"y)/("d"x) - y/x = x`
Solve the following:
`("d"y)/("d"x) + (3x^2)/(1 + x^3) y = (1 + x^2)/(1 + x^3)`
Choose the correct alternative:
Which of the following is the homogeneous differential equation?
A manufacturing company has found that the cost C of operating and maintaining the equipment is related to the length ’m’ of intervals between overhauls by the equation `"m"^2 "dC"/"dm" + 2"mC"` = 2 and c = 4 and when = 2. Find the relationship between C and m