2. Derivation of triangle area formula: put two identical triangles into a parallelogram.
3. Derivation of trapezoid area formula: Put two identical trapezoids into a parallelogram.
4. Derivation of circle area formula: Transform a circle into an approximate rectangle.
5. Derivation of cylinder volume formula: transforming cylinder into cuboid.
6. Put all ten or one hundred methods together in a simple calculation. Such as: 253-99=253- 100+ 1.
7. Transformation of numbers and formulas: 25× 16=25×4×4 16 is transformed into 4×4.
8. Number to number conversion:1÷ 0.125 =1÷1/8
Knowledge related to the idea of mathematical reduction in primary schools;
Transforming thinking is to transform an unknown (to be solved) problem into a solved or easy-to-solve problem, such as simplifying the complex, changing the difficult to the easy, changing the unknown to the known, and changing the high order to the low order. It is one of the most basic problem-solving ideas and one of the basic thinking methods of mathematics.
In teaching, we often encounter cases that need to use "transforming ideas". For example, calculate 98×35, and convert 98 into 100-2, which can be simplified as: 98× 35 = (100-2 )× 35 =100× 35-2× 35 = 3430.