"Square Root" PPT Courseware 7

Description

"Square Root" PPT Courseware 7

Knowledge review

⑴ The square root of 25 is ±5.

⑵ The square root of 81 is ±9.

⑶ The square root of 49/64 is ±7/8.

⑷ The square root of 0 is 0.

⑸ Does -4 have a square root?

arithmetic square root

The positive square root √a of a positive number a is called the arithmetic square root of a

Rule: The arithmetic square root of 0 is 0

Improve understanding

Determine the correctness of the statement and explain the reasons

(1) 5 is the arithmetic square root of 25

(2) The arithmetic square root of 36 is -6

(3) Negative numbers do not have square roots but have arithmetic square roots.

(4) If a is the arithmetic square root of x, then a must be the square root of x

(5) If a is the square root of x, then a must be the arithmetic square root of x

(6) The arithmetic square root of a number must be a positive number

(7) The arithmetic square root of a number must be a non-negative number

(8) If the arithmetic square root of m is n, then its other square root must be -n

Example analysis

For example: There is a rectangular lawn in a certain community. In order to enhance protection, the community management staff plans to surround it with a fence along the edge of the lawn. It is known that the length of the rectangular lawn is 4 times the width and the area of ​​the lawn is 900m2. Find the total length of the required fence.

Solution: Assume the width of the lawn is xm, then the length is 4xm.

4x·x=900

x2＝225

∴ x＝±√225＝±15

x = -15 does not meet the meaning of the question, discard it

∴ x =15, 2×(15+4×15)=150(m)

Answer: The total length of the required fence is 150m.

Expand and deepen

(1)The arithmetic square root of √81 is __________.

(2) The number whose arithmetic square root is equal to itself is _____.

(3) If √x=2, then x=

(4) It is known that √x-4 + |2y+5|=0, then x＝＿＿, y＝＿＿.

Operation

1. Questions 1-4 of Group A on page 65 of the textbook

2. Synchronization Exercise Book 14.1 (2)

Keywords: square root teaching courseware, Hebei Education Edition eighth grade mathematics volume PPT courseware download, eighth grade mathematics slide courseware download, square root PPT courseware download, .PPT format;

For more information about the "Square Root" PPT courseware, please click the Square Root ppt tab.

"Square Root" PPT courseware 9:

"Square Roots" PPT Courseware 9 Learning Objectives 1. Be able to tell the meaning of arithmetic square roots, and be able to use symbols to represent the arithmetic square roots of positive numbers. (Key Points) 2. Be able to use square operations to find the arithmetic square roots of certain non-negative numbers. (Key Points) 3 . Be able to understand and apply the properties of square roots in arithmetic..

"Square Root" PPT courseware 8:

"Square Root" PPT Courseware 8 [Learning Objectives] (Only when you have a goal in mind will you have a direction in learning) 1. Understand the definition of square root, master the properties of square root, and use the root sign to represent the square root of a number. 2. Know that the square root and the square are mutually exclusive The inverse operation will make use of this reciprocal operation.

"Square Root" PPT courseware 6:

"Square Root" PPT courseware 6 1. Definition of square root (1) Generally, if ______ of a number is equal to a, then this number is called the square root or quadratic root of a. That is to say, if x2=a, then x is called the square root of a. (2) Find a number a ..

File Info

Update Time: 2024-09-14

This template belongs to Mathematics courseware Hebei Education Edition Eighth Grade Mathematics Volume 1 industry PPT template

Preview