As you've indicated, reduce the order for 1 and 2. For 3, note that (yy')' = LHS. Then integrate. For 4, just integrate directly once. You'll get a first-order separable equation out of that.
I know we can use the subsittion of m = y' for 1 and 2, then let y'=m(y(t))for 3 and 4, but I have a hard time to solve for the answer
as the answers are given, can anyone show me the setps, I need to undertsand this for the test tomorrow
the question is inside the image and
tha answers are