Solving by substitution

When Solving by substitution, there are often multiple ways to approach it. Wherein: The slide rule has been widely used for nearly two centuries until 1642, when Pascal, a French mathematician, physicist and chemist, invented a mechanical computing machine - roller adder, also known as Pascal calculator, in order to reduce his father's heavy tax calculation burden..

The other equations are solved by decoupling in the separation algorithm; Because the momentum and continuity equations are solved in a tightly coupled manner, the convergence speed of the solution is significantly improved compared with the separation algorithm. However, since all discrete systems based on momentum and pressure continuity equations must be stored in memory when solving the velocity field and pressure field (instead of storing only one equation like the separation algorithm), the storage requirement increases by 1.5-2 times as much as that of the separation algorithm. 3. The branch voltage method takes the branch voltage as the solution variable, uses the branch voltage to represent the current of each branch, writes the corresponding KVL equation, and solves the equation. For this equation, we can first look at the form of the solution.

Basically, I wrote this answer because there was no physical thinking and scientific thinking. We know the object, one is measurement, the other is mathematics. The measurement method uses instruments to measure the external characteristics of the object, and then carries out data analysis. Mathematical method, using mathematical tools to establish functions and equations, and then analyzing the properties of functions (monotony, boundedness, symmetry, continuity, concavity and convexity, inflection points, algorithms, limits, median values, extreme values, frequencies, components, etc.), solving equations, etc..

Such an equation definition, and then in teaching, we start to pick words that contain unknowns, that is, letters, and equations, that is, =. After deduction, we will start to give some formulas for judgment. I've never studied this definition before. What's wrong with this kind of practice? Now I think back to some of the children's mistakes in the teaching process.

Every day, we use wechat groups for online communication and interaction, carefully prepare lessons, set up teaching links, arrange homework... Every step should be polished carefully. After the centralized discussion, we will conduct interactive Q & A, exchange and discussion, supplement and improve the collection of effective questions. The daily teaching and research activities make us grasp the teaching materials more deeply, point out the direction, clarify the ideas and lay a foundation for our next classroom teaching.