"Understanding Irrational Numbers" Real Numbers PPT Download

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"Understanding Irrational Numbers" Real Numbers PPT Download

Part One: Learning Objectives

1. Understand the basic concepts of irrational numbers. (emphasis)

2. Use a calculator to estimate the approximate value of an irrational number.

Understanding irrational numbers PPT, part 2: introducing new lessons

Situation introduction

Xiaohong is a freshman who has just entered eighth grade. One weekend morning, her father, who is an engineer, gave Xiaohong a math problem: From a square wooden board with a side length of 6cm, cut off four identical right angles as shown in the figure. Triangle. Please calculate the area of ​​the remaining square plank? What is the length of the side of the remaining square plank in centimeters? Have you ever seen this number? Can you help Xiaohong solve this problem?

Understanding Irrational Numbers PPT, Part 3: Teaching New Courses

Understanding of irrational numbers

activity exploration

Activity: Cut and join two small squares with side length 1 to get a big square. Can you?

There are many other ways! Give it a try in your spare time and see who can find more!

Question 1: Suppose the side length of the large square is a, what conditions does a satisfy?

Because S is a large square = 2, so a2 = 2.

Question 1: What kind of number is a? Is it possible that a is an integer?

Question 2: Could a be a fraction?

① Is a a fraction with a denominator of 2?

② Is a a fraction with a denominator of 3?

③ Is a a fraction with a denominator of 4?

④ a is a fraction with a denominator?

Induction: a is neither an integer nor a fraction, so a is not a rational number.

think about it

(1) Will the square of side length a be exactly equal to 2 when counted to a certain digit? Why?

(2) Is it possible that a is a finite decimal? What kind of number will it be?

a=1.414 213 56…, it is an infinite non-repeating decimal

Do it

Estimate the value of the side length b of a square with area 5, and the result is accurate to the percentile.

b=2.236067978…, it is also an infinite non-repeating decimal

Understanding irrational numbers PPT, part 4: practice in class

1. Among the following numbers: (the number of 0s between two adjacent 3s is added one by one), the number of irrational numbers is ( )

A.2 B.3 C.4 D.5

2. Among the following numbers, which one is an irrational number ( )

A. 3.14 B. C. D.

3. True or False Questions

(1) Finite decimals are rational numbers; ( )

(2) Infinite decimals are all irrational numbers; ( )

(3) Irrational numbers are infinite decimals; ( )

(4) Rational numbers are finite decimals. ( )

Understanding Irrational Numbers PPT, Part 5: Class Summary

The concept and understanding of irrational numbers

Use a calculator to approximate irrational numbers

Keywords: Beijing Normal University edition eighth grade mathematics PPT courseware free download, understanding of irrational numbers PPT download, real numbers PPT download, .PPT format;

For more information about the "Real Numbers Understanding Irrational Numbers" PPT courseware, please click on the Real Numbers PPT Understanding Irrational Numbers PPT tag.

"Understanding Irrational Numbers" real number PPT teaching courseware:

"Understanding Irrational Numbers" Real Number PPT Teaching Courseware Part One: Learning Objectives 1. Understand the definition of irrational numbers and be able to determine whether a number is an irrational number. Distinguish the difference between rational numbers and irrational numbers. 2. Use the calculator to explore that irrational numbers are infinite non-repeating decimals. ..

"Understanding Irrational Numbers" Real Numbers PPT:

"Understanding Irrational Numbers" Real Numbers PPT Part One: Knowledge Points Basic Knowledge Point 1 Irrational numbers in life and estimating the size of irrational numbers 1. The length and width of a rectangle are 6 cm3 cm respectively, then the length of its diagonal is (D) A. Integer B. Fraction C. Rational..

"Understanding Irrational Numbers" Real Numbers PPT Courseware 3:

"Understanding Irrational Numbers" Real Numbers PPT Courseware 3 Learning Objectives 1. Understand the concept of irrational numbers and be able to determine whether a number is a rational number or an irrational number. 2. Be able to represent some simple irrational numbers on the number axis. In fact, any rational number can be written as a finite decimal Or infinite loop...

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Update Time: 2024-09-08

This template belongs to Mathematics courseware Beijing Normal University Edition Eighth Grade Mathematics Volume 1 industry PPT template

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