September 2016

Please help. I need it asap.

Solve the linear differential equation:
(D5–12D4+52D3–112D2+192D–256)y = 0

When I factored it out. I got (D-4)^3 (D^2 +4)

With D-4..

My equation will be Y= (C1 + C2x + C3x^2)e^4x

But how about my D^2 + 4?

How can I add that in my equation?

(y^4 - 2xy) dx + 3 x^2 dy= 0

( 2x³ - y⁴) dx + xy³ dy= 0

[(1-xy)^-2]dx + [y^2-x^2(1-xy)^-2]dy=0 ;when x=1, y=1

find a general solution

dx/dy =[ -2x (csc 2y – 2x³ cos 2y)] / sec 2y

(This problem is from CE Ref V4 of Gillesania)

A quadrilateral ABCD is inscribed in a semicircle with side AD as the diameter. If point O is the center of the diameter, determine the angle DCO if angle CAD is 39 deg.

In the book's solution, it says that angle COD = 2 times angle CAD. Is this a rule in semi circles?

(Attached is the drawn image of the problem)

Thanks in advance mga sir.

https://drive.google.com/open?id=0BzglifbmrqfKOUtqSFZEWnNYNVE

In how many ways can 4 girls and 4 boys be seated in a row containing 8 seats if boys and girls must sit in alternate seats?
The answer in my notes is 1,152..
I need a solution please.
Thanks in advance.