Q18 · 2023 · Technology-freeComplex unfamiliar6 marks
QUESTION 18 (6 marks)
A particular solution to the differential equation
where and , passes through the origin.
Determine this solution in the form . Leave your answer in simplified form.
WORKED SOLUTION
6 marksQCAA guide · typeset solution
ANSWER
.
Worked solution
Separate variables:
Thus
Using gives . Exponentiating gives , so . Since and , , hence
separates the variables
uses suitable integration
determines the constant of integration
determines an expression with no logarithms
expresses in terms of
evaluates the reasonableness of the solutions using the restrictions and gives the simplified form
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