7/9, 1/3,- 1,-5,()
Poor: .......... -4/9,4/3, -4.
Poor: ............... 16/9,-16/3.
-16/3× 2-16/9 =-112/9, counting up,-112/9-4 =-/kloc-.
2(3.6-3 times) = x-2+3 times -3.8
7.2-6 times = 4-5.8 times
13= 10x
x= 1.3
Teaching focus
Fill in the blanks with rules, and let students find the simple arrangement rules of figures and numbers through observation, experiment, guessing and reasoning.
The significance of finding the law to fill in the blanks is actually to strengthen the understanding of the general law of sequence. Although it has many solutions, it is mainly to cultivate your ability to find the general law of series and guess the general term of series (that is, the ability to use incomplete induction), so that when you encounter some series that are difficult to find the general term by general methods, you can guess the general term formula of this series quickly and accurately through the first few terms.