Differential Equations/Expert Profile

Average Ratings

• Knowledgeability 9.86
• Clarity of Response 9.78
• Politeness 9.90
• Response Time(hr) 47.2
• Response Time(hr, last 90 days) 22.9

• Number of Questions Today 0
• Max Questions to be Asked in a Day 5
• Total Questions (since joining AllExperts) 171
• Volunteer Since 2010-04-05
• Prestige Points 1680

Recent Reviews from Users

Read More Comments

Recent Answers from Dr Paul Safier

2011-10-07 systems of diffrantial equations:

Sajjad,     OK, thanks. So this is a system of two ordinary (not partial) differential equations for x(t) and y(t). The second equation is nonlinear because of the y^2 term. The system would be quite easy

2011-10-07 systems of diffrantial equations:

Hi Sajjad,     I'm not seeing that this is a partial differential equation. Can you clarify what you mean by the notation, Dx and Dy? Is that dx/dt and dy/dt?     Whether this is a partial or ordinary

2011-09-23 differential equations:

J,     Your equation is close to being exact, but not quite. To make it exact, you multiply each term by an integrating factor. In this case, use -1/(y^2). Follow the instructions in the link below for

2011-09-13 decay and growth rate:

J,     The differential equation is separable, so move the term with P over to the left and integrate both sides to get:    -ln[P-1] + ln[P] = -r/b exp[-b t] + C, where I've used 'b' to denote infinity

2011-08-14 Particular Solution of the ODE:

Jay,     The way I chose to handle that integral was to rewrite the cos^2(2x) term using the identities.     Use the identity cos(a+b)=cos(a)*cos(b) - sin(a)*sin(b) with a=2x and b=2x to get     cos(4x)=cos^2(2x)