Concept:The order of a differential equation is the highest derivative present; the degree is the power of that highest derivative after the equation is expressed as a polynomial in derivatives.
Explanation:The given equation is
(dx3d3y)32−3dx2d2y+5dxdy+4=0The highest order derivative present is
dx3d3y, so the order is
3.
However, the highest derivative has a fractional power
32, so the degree cannot be read directly.
Rearrange the terms by moving everything except the fractional power term to the right side:
(dx3d3y)32=3dx2d2y−5dxdy−4Now cube both sides to remove the fractional power:
(dx3d3y)2=(3dx2d2y−5dxdy−4)3Now the equation is a polynomial in derivatives. The highest order derivative
dx3d3y has power
2.
Hence, the degree is
2.
Answer:The order is
3 and the degree is
2, so the correct option is B
(3,2).