Урок математики в 7 классе по теме:"Степень с натуральным показателем"

1. Good afternoon, dear children and guests! Today we have an interesting lesson again. We are going to speak both English and Russian. I hope that you’ll work hard. Let Pythagoras help us all! 2. Let’s start with math workout. a) Oral account : 23 , 34 , 112 and so on. b) Represent next numbers as numbers raised to a power 27,144, 64,81 ,225, 625 and so on. 3. Take sheets of paper (cards)(one for two). And write some degree (one degree) ,using 1 row-whole numbers 2 row-ordinary fractions 3 row-decimals Using negative and positive numbers. Come out to the blackboard You must take only those cards where the value of the degree is negative. Check your choice. Please count. Is his answer correct?(is everything correct? Correct mistakes , your variant) Now those who still have cards stand up , read your degree and find its value. 4. Now look at the blackboard. You are being offered the row of numbers: 128,27,81,16,64,1,243,9,32. You must choose 1 variant- number which can be represented as a degree of the base 2 2 variant- number which can be represented as a degree of the base 3 Who wants to go to the blackboard and write results? 5. Repeat properties of degrees am∙an=….. am:an=….. (¿¿m)n=….. a ¿ (ab)m =….. (a b)m =… Come out to the blackboard. You should make true equalities using cards and tell us about them. 6. Classwork The next task. Please fill in the gaps in these expressions and write them down in your exercise books. a) x7 ¿ =x4 d) х7∙х¿=х7 g) (х у)¿ = х5 у5 b) ¿∙х2=х6 e) (х3)¿=х12 c) (ах)8=а8∙∗¿ f) 0,512∙212 = (¿ )12 You have three minutes for the work. Check your results. Those who made everything correct, raise hands. 8. Simplify the expressions using properties of degrees: а) x7∙x2∙x x3∙x4 b) x15∙a11 a8∙x10 c) a9∙(b3)2 (a2)4∙b5 d) (xy6)4 (x3y5)2 e) 58∙38∙149 157∙210∙710 9. The time has come to check how erudite you are. Try to answer my questions. If you can’t, I offer you to solve a sum to know the answer. a) This number is the most perfect according to Pythagoras. −32−(−3)4:92 +15 ∙20 =5 b) Well known search system GOOGLE got its name from this number. 1098∙10−34∙1030∙106=10100 c) In Great Britain people type this number in messages if they want to tell that they have no money. 199+(−3)3∙(−1)78+24+45=35 d) Слово цифра (digit) исходит от арабского «цифр». What does it mean? −25:22+23=0 10. Let’s play. I tell a degree and then a student has to show the corresponding value in the table. You have to be quick. We play till the first mistake. The winner is the one who will have more correct answers than others. 121 81 9 64 128 27 169 225 8 1 243 625 32 16 1000 196 144 49 100 4 The lesson is over. Thank you for your work. Good bye. целые числа десятичная дробь строка ошибка 1. workout разминка to solve a sum решить пример 2. oral account устный счёт one for two один на двоих 3. number число whole numbers 4. ordinary fraction обыкновенная дробь decimal 5. row ряд line 6. digit цифра mistake 7. negative отрицательный positive положительный right now прямо сейчас correct исправить 8. numerator числитель denominator 9. choice выбор degree ,power 10. exponent показатель степени base two in the fifth degree 25 four squared знаменатель степень основание 11. 42 12. four in the cubed 43 raise to a power возвести в степень odd нечётный 13. чётный 14. one second ( one half ) 2 3 even 1 2 two thirds 15. < less than меньше чем > more than multiplied by умноженный на divided by больше чем 16. делённый на 17. find the value of the expression найти multiplication degrees with the same base умножение выражения значение 18. степеней 19. с одинаковыми основаниями division degrees with the same base деление степеней с одинаковыми основаниями 20. raising the ratio in the degree (to the power) возведение 21. raising degree into degree (to the power) возведение raising product into degree (to the power) возведение represent as a degree of the base представить степени с основанием в виде частного в степень в степень степени 22. произведения 23. в степень property of the degree свойство simplify the expression упростить 26. make true equality составить fill in the gaps 24. 25. степени выражение верное равенство 27. заполнить пропуски “BEST” Lycee OPEN MATHS LESSON “DEGREE WITH NATURAL EXPONENT” Teacher: Bogovik T.A. 2013 областной семинар на тему :«Особенности проектирования современного урока математики в контексте полиязычного образования».