Applied Calculus: UNIT II: Functions of Several Variables

Partial derivatives: Problems under type-3

Explanation, Formula, Equation, Example and Solved Problems - Partial derivatives: Problems under type-3

PROBLEMS UNDER TYPE 3

 

If f(x, y) = 0 is given, dy/dx = ‒fx/fy where fx = ∂f/∂x, fy = ∂f/∂y.


 

Example 29. If 2x2+6xy +4y2+6x+8y + 9 = 0, then find dy/dx using partial derivatives.

Solution: Given f(x, y) = 2x2 + 6xy + 4y2 + 6x + 8y + 9

fx = 4x+6y+6; fy=6x+8y+8

dy/dx = ‒fx/fy =  ‒(4x+6y+6) / 6x+8y+8

= ‒2(2x+3y+3) / 2(3x+4y+4)

dy/dx = ‒(2x + 3y+3) / 3x + 4y +4

 

Example 30. Find dy/dx using partial derivatives if x3 + y3 = 3ax2y.

Solution: Given f(x, y) = x3+ y3‒3ax2y

fx = 3x2‒6axy;

fy = 3y2‒3ax2


 

Example 31. Find dy/dx if x3 + y2 = 3axy.

Solution: Given f(x, y) = x3 + y3 ‒ 3axy

fx = 3x2 ‒ 3ay; fy = 3y2 ‒ 3ax


 

Example 32. If xy + yx = c, then find dy/dx.

Solution: Given xy + yx = c.

Let f(x, y) = xy + yx ‒ c

fx = yxy‒1 + yxlogy;

fy = xylogx + xyx‒1


 

Example 33. If x sin(x − y) ‒ (x + y) = 0, use partial differentiation to prove dy/dx = 

Solution: Given f(x, y) = x sin(x − y) ‒ (x + y)

f/∂x = xcos(x − y) + sin(x − y) – 1

f/∂y = xcos(x − y)(− 1) − 1



 

 

Applied Calculus: UNIT II: Functions of Several Variables : Tag: Applied Calculus : - Partial derivatives: Problems under type-3


Applied Calculus: UNIT II: Functions of Several Variables



Under Subject


Applied Calculus

MA25C01 Maths 1 M1 - 1st Semester | 2025 Regulation | 1st Semester 2025 Regulation



Related Subjects


English Essentials I

EN25C01 1st Semester | 2025 Regulation | 1st Semester 2025 Regulation


தமிழர் மரபு - Heritage of Tamils

UC25H01 1st Semester | 2025 Regulation | 1st Semester 2025 Regulation


Applied Calculus

MA25C01 Maths 1 M1 - 1st Semester | 2025 Regulation | 1st Semester 2025 Regulation


Applied Physics I

PH25C01 1st Semester | 2025 Regulation | 1st Semester 2025 Regulation


Applied Chemistry I

CY25C01 1st Semester | 2025 Regulation | 1st Semester 2025 Regulation


Makerspace

ME25C04 1st Semester | 2025 Regulation | 1st Semester 2025 Regulation


Computer Programming C

CS25C01 1st Semester | 2025 Regulation | 1st Semester 2025 Regulation


Computer Programming Python

CS25C02 1st Semester | 2025 Regulation | 1st Semester 2025 Regulation


Fundamentals of Electrical and Electronics Engineering

EE25C03 1st Semester | 2025 Regulation | 1st Semester 2025 Regulation


Introduction to Mechanical Engineering

ME25C03 1st Semester | 2025 Regulation | 1st Semester 2025 Regulation


Introduction to Civil Engineering

CE25C01 1st Semester Civil Department | 2025 Regulation | 1st Semester 2025 Regulation


Essentials of Computing

CS25C03 1st Semester - AID CSE IT Department | 2025 Regulation | 1st Semester 2025 Regulation


Applied Physics I Laboratory

PH25C01 1st Semester practical Laboratory Manual | 2025 Regulation | 1st Semester Laboratory 2025 Regulation


Applied Chemistry I Laboratory

CY25C01 1st Semester practical Laboratory Manual | 2025 Regulation | 1st Semester Laboratory 2025 Regulation


Computer Programming C Laboratory

CS25C01 1st Semester practical Laboratory Manual | 2025 Regulation | 1st Semester Laboratory 2025 Regulation


Computer Programming Python Laboratory

CS25C02 1st Semester practical Laboratory Manual | 2025 Regulation | 1st Semester Laboratory 2025 Regulation


Engineering Drawing

ME25C01 EEE Mech Dept | 2025 Regulation | 2nd Semester 2025 Regulation


Basic Electronics and Electrical Engineering

EE25C04 1st Semester ECE Dept | 2025 Regulation | 2nd Semester 2025 Regulation