## Kronecker delta: How to write scalar product in index notation

Here you learn everything about Kronecker-Delta! Including 4 calculation rules with Einstein's summation convention, typical mistakes and more.

Advanced tools from mathematics for physicists.

Level 3 requires the basics of vector calculus, differential and integral calculus. Suitable for undergraduates and high school students.

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Lesson ## Kronecker delta: How to write scalar product in index notation

Here you learn everything about Kronecker-Delta! Including 4 calculation rules with Einstein's summation convention, typical mistakes and more.

Video ## Kronecker delta explained simply in 11 minutes!

In this video you will learn the Kronecker delta within 10 minutes and how you can use it to write down the scalar product in index notation.

## Quests with solutions

Exercise with solution ## Simplify expressions with Kronecker delta

Here you practice the properties of the Kronecker delta by simplifying given expressions as much as possible.

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Lesson ## Differential equations (DEQ): Important basics + 4 solving methods

Here you will learn the basics of differential equations (DGL), what types there are (ordinary, partial, linear, homogeneous) and 4 solving methods (separation of variables, variation of constants, exponential and separation ansatz).

Video ## Differential Equations explained simply in 47 minutes!

In this Lecture you will learn to classify and to solve arbitrary differential equations (ODE / PDE) in 42 minutes.