i need help with some of these, i kind of know how to do it, but i get stuck...

1. dy/dx = (ycosx)/(1+y^2) y(0)=1

i know how to get to the integral of both sides what to i do becuase i get a y^2 on the left?

we are supposed to solve the equation using the values given..

2. dz/dt + e^(t+z)

im not sure how to separate the equations here

3. dp/dt = sqrt(pt) p(1) = 2

im not sure if i got this right but i got p = sqrt (1/4sqrt(t) + 15/4)

please help!! thankss!