Originally Posted by

**thermalwarrior** Could some one check these for me please?

1) dy/dx = (3/x)*y + 5x^2 (x>0)

What is the integrating factor?

Answer = x^3 Mr F says: No. It's 1/x^3.

2) d^2y/dx^2 - 16y =4e^-4x has the complementary function y = ae^4x + be^-4x

What is a suitable particular integral?

Answer = y = ae-4x Mr F says: No. This particular solution is part of the homogenous solution. It will therefore make the left hand side of the DE equal to zero ..... Try again .....

Think these are right but not sure. Thanks in advance!!!

N.B read a = alpha and b = beta