Differential Equations Answers

Could you please explain how to solve differential equations using matrices. I understand that it somehow involves eigenvalues and eigenvectors. I am not familiar with either eigenvalues or eigenvectors....

I need to find the partial derivatives of f(x,y) = xy / sqr(x²+y²).
Thanks for your help.

on march 16 three boys went to the store they each bought 5dallors to spend they left for the store at 9oclock the got back home at 12 oclock how muck money did they have to spend in all

anti derivative of 5/(x^2) -7/(x^3) + 9/(x^4)

antidervative of 3/2x+1

Antiderivative of (2x+1)^(1/2)

first derivative and second derivative of f(x)= e^(1/x)

If y = e^ax cos^3 x sin^2 x find dy/dx

Differentiate f(x)= e^x/x^2

I'd like to know how i can tackle this question because its getting me confused:
" The curve y =1/a + bx passes through the point (1, -1) and its gradient at that point is 2. Find values of a and b