In this lecture, we systematically introduce and explore the Inverse Function Theorem in the context of both single-variable and multivariable calculus. The presentation begins with a geometric and conceptual motivation rooted in the horizontal line test and local invertibility, before transitioning into a formal statement of the theorem for functions f : R^n to R^n.
We examine several carefully chosen examples to illustrate when and how a function can be locally inverted, and discuss how the Jacobian matrix becomes a central diagnostic tool. We also highlight how to compute the Jacobian of the inverse function without solving for the inverse explicitly
#mathematics #realanalysis #advancedcalculus #multivariablecalculus #inversefunctions #jacobian #differentiability #differentialcalculus #maths