"Concept and Properties of Circle" PPT courseware

Description

"Concept and Properties of Circle" PPT courseware

1. As shown in the figure, the ________ composed of all points on the plane whose distance from the fixed point O is equal to a fixed length (the length of OA) is called ________, the fixed point O is called ________, and the line segment OA is called the ________ of the circle.

2. A circle is an axially symmetrical figure, and every ________ that passes through the center of the circle is its ________. A circle is also a centrally symmetrical figure, and ________ is its center of symmetry.

3. The line segment between any two points on a circle is called a ________ of the circle, and the chord passing through the center of the circle is called the ________ of the circle. The part between any two points on the circle is called _________, or _________ for short. The diameter of a circle divides the circle into two arcs that completely overlap. Such an arc is called ________. An arc larger than a semicircle is called ________, and an arc smaller than a semicircle is called ________.

4. Two circles that can overlap are called ________, and two arcs that can overlap are called ________.

1. (4 points) As shown in the picture, in the physical education class, Xiaoli’s shot put score was 6.4 m. The shot put she threw fell on ()

A． Area ① B. Area②

C. Area ③ D． Area④

2. (4 points) Among the following conditions, which one can determine the circle is ()

A． Take point O as the center of the circle

B． Take 2 cm length as radius

C. Take point O as the center of the circle and the length of 5 cm as the radius.

D. passing through known point A

14. (10 points) As shown in the picture, a unit is conducting blasting operations around lighthouse A. The waters within 3 km around A are dangerous areas. A fishing boat mistakenly entered point B 2 km away from point A. In order to leave the dangerous area as soon as possible, the Which ray should the ship sail along? Please explain the reason.

The ship should sail away from the danger area in the direction of ray AB. Reason: Suppose ray AB intersects ⊙A at point C, pick any point D on ⊙A (excluding the symmetry point of C about A), connect AD, BD. In △ABD, AB+BD>AD, ∵AD=AC= AB+BC, ∴AB+BD>AB+BC, ∴BD>BC

15. (10 points) As shown in the figure, AB and CD are the two diameters of ⊙O, E and F are the midpoints of OA and OB respectively. Prove that the quadrilateral CEDF is a parallelogram.

It can be proved that OE=OF

16． (10 points) As shown in the figure, CD is the diameter of ⊙O, point A is on the extension line of DC, AE intersects ⊙O at point B, AB is equal to the radius of ⊙O, ∠DOE=78°, find the degree of ∠A.

Suppose ∠A＝x, ∵∠A＋∠E＝∠DOE＝78°,

∴∠E＝78°-x, ∵OB＝OE,

∴∠OBE＝∠A＋∠BOA＝2∠A.

∴2x=78°-x,

∴x=26°, that is, ∠A=26°

17． (10 points) As shown in the figure, AB is the diameter of ⊙O, and CD is the non-diameter chord in ⊙O. Can you determine the relationship between AB and CD?

AB>CD, connect OC, OD, and use the relationship between the three sides of the triangle to determine

Keywords: teaching courseware on the concept and properties of a circle, download the mathematics PPT courseware for the first volume of the ninth grade of Hebei Education Edition, download the mathematics slide courseware for the ninth grade, download the PPT courseware on the concept and properties of a circle, .PPT format;

For more information about the "Concept and Properties of Circles" PPT courseware, please click on the "Concept and Properties of Circles" ppt tab.

File Info

Update Time: 2024-10-19

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

Preview