(x2 + y2)dx + x(x − 2y)dy = 0
solve ( 3x y^3 + 2y )dx + (2x^2 y + x ) dy = 0
1/xy2+y4 is an integrating factor for the differential equation (x2y+y2)dx+(y3-x3)dy=0.
y1/x
Given the partial differential equation 𝑈𝑡 + 𝑈𝑥𝑥 = 0, 0 < 𝑥 < 𝜋,𝑡 > 0. Use the method of separation of variables to solve the given equation with the following conditions. 𝑈𝑥 (0,𝑡) = 0,𝑡 > 0
𝑈𝑥 (𝜋,𝑡) = 0,𝑡 > 0 𝑈(𝑥, 0) = 𝑥(𝜋 − 𝑥), 0 < 𝑥 < 𝜋
The temperature of air is 30°C, and the substance cools from 100°C to 70°C in 15 minutes. Find the temperature after 20 min.
solve dx/2x(y+z^2) = dy/y(2y+z^2) = dz/z^3
find the general solution of the equation 2x(y+z^2)p+y(2y+z^2)q=z^3. and deduce that
yz(z^2+yz-2y)=x^2 is a solution
y''+4y=cos^2(x)
(𝟐𝒙𝒚 − 𝒚^ 𝟐 + 𝒚)𝒅𝒙 + (𝟑𝒙^𝟐 − 𝟒𝒙𝒚 + 𝟑𝒙)𝒅𝒚 = 𝟎
(x+y-4)dx-(3x-y-4)dy=0 when x=4 and y=7.