Description
DSolve is a differential equation solver.
The derivative of the variable is notated using derivative notation. MathStudio uses the single quotation character to represent the derivative of a variable or function.
f'(x) - First derivative
f''(x) - Second derivative
f'''(x) - Third derivative
Derivative Examples
Solve: y' + y = sin(t)
DSolve(y'(t)+y(t)=sin(t), y(t), .....)
Solve: y'' + 2y' + y = x
DSolve(y''(x)+2y'(x)+y(x)=x, y(x), .....)
The definite integral of the variable is represented by I(f(t), t) and denotes the integral of the variable f(t) with lower bound 0 and upper bound t. These bounds cannot be changed.
Integral Examples
∫(y) + y = sin(t)
DSolve( I(y(t),t) + y(t) = sin(t), y(t), .....)
The upper case character I indicates the integral and is a mandatory condition.
Initial values
When no initial values are given, then simple write the word no. The result returned contains the Constant C@_1.
For first order differential equations the initial value can be given as y(t)=value. When you ommit y(t), then y(0) is assumed.
For higher order differential equations, the initial values should be given as a list and are always referred to zero : [y(0), y'(0), y''(0), ...]
Examples with different initial values
Solve: y' + y = sin(t) with y(0) = 5
DSolve(y'(t) + y(t) = sin(t) , y(t) , y(0) = 5)
or
DSolve(y(t)' + y(t) = sin(t) , y(t) , 5)
Solve: y' + y = sin(t) with y(2) = 5
DSolve(y(t)' + y(t) = sin(t) , y(t) , y(2)=5)
Solve: y'' + 2y' + y = x with y(0) = 1 and y'(0) = 2
DSolve(y''(x) + 2y'(x) + y(x) = x, y(x), [1,2])
Solve: y'' + 2y' + y = x with no initial values
DSolve(y''(x) + 2y'(x) + y(x) = x, y(x), no)
Different form for exact first order differential equations.
Exact first order differential equation can be given with d@_x , d@_t , d@_y, ect.
First Order Examples
Solve: dy = sin(t) * dt
DSolve(d@_y = sin(t) * d@_t, y(t), .....)
Of course, this can also be written as the following equation.
DSolve(y'(t) = sin(t) , y(t), ...)
Note: The variable to be solved should still be written as y(t).
Results
Normally, DSolve tries to return the result as y(t) = function(t).
In case y(t) cannot be represented in a simple form then the result is returned in implicit form.
function(y , t) = 0
In the latter case, the text Implicit result is added to call the users attention that the result is not of the form y(t)=function(t).
