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MathsMediumClass 12

Implicit Differentiation

Differentiation

2

JEE Qs

8%

Hard

60

min

Master the application of the chain rule to 'y' terms and practice meticulous algebraic manipulation to correctly isolate dy/dx.

🧮 Key Formulas

d/dx (f(y)) = f'(y) * dy/dx
d/dx (y^n) = n*y^(n-1) * dy/dx
d/dx (sin(y)) = cos(y) * dy/dx
d/dx (e^y) = e^y * dy/dx
d/dx (ln|y|) = (1/y) * dy/dx

✅ Key Points for JEE

  • 1When differentiating an equation implicitly, treat 'y' as an unknown function of 'x' (i.e., y = f(x)).
  • 2Differentiate both sides of the equation with respect to 'x'.
  • 3Apply the chain rule whenever differentiating a term involving 'y'; always multiply its derivative by dy/dx.
  • 4After differentiating, rearrange the equation algebraically to isolate dy/dx.
  • 5Remember to apply product rule (d/dx(uv) = u'v + uv') for terms involving products of x and y (e.g., xy) and quotient rule if necessary.

⚠️ Common Mistakes

  • Forgetting to multiply by dy/dx when differentiating a term containing 'y' with respect to 'x'.
  • Incorrectly applying the product or quotient rule for terms involving both 'x' and 'y' (e.g., d/dx(x*y)).
  • Algebraic errors in collecting terms and isolating dy/dx.
  • Treating 'y' as a constant or 'x' as a constant during differentiation, instead of an implicit function.

NCERT Chapters

  • Class 12 Mathematics Ch 5: Continuity and Differentiability