三年级数学第一学期复习提纲docx.docx

1、三年级数学第一学期复习提纲docx三年级数学第一学期复习提纲Syllabus for the first semester of grade three mathematicsUnit 11, recursive equation is cleverAdd brackets: the fro nt is plus sign, followed by parentheses, constant numberThe front is a minus sign, followed by brackets, you want to cha nge.Shift position: the sign mo

2、ves along with the numbers behind.2, for maximum difference, minimum differenceThe biggest difference: (1) to create a maximum number (2) to create a minimum (3) vertical subtractionThe minimum difference: (1) to create a minimum of two digits on the minuend after two (2) to create maximum two digit

3、s in two after meiosis(3) the rest of the adjacent select number of large put hundreds of small minuend, put hundreds of bits (4) vertical subtraction3, subtraction tower(1) to create the largest and smallest numbers with three card number, vertical subtraction(2) the difference between the obtained

4、 difference and the arithmetic number is the same, and the end of the subtraction tower is not the same, then repeat the number (1) with the difference number until the sameSecond unit1, the entire 100, the multiplication and division decamerous2, Division is the inverse operation of multiplication3

5、, the application should be in a number of conditions, according to the problem to choose useful conditions, and then column calculations4, a single digit multiplied by two digits, three digitsA and spin off calculation(1) two digits: two digits split TENS (ten) and a number (a few), and one digit a

6、re multiplied by two (2) product is the sum of three digits: three digits split into a whole hundred (several hundred), ten (ten) and a number of (a few), and one digit are multiplied by three is the sum of productB, vertical calculation(1) were written by digital alignment (2) more than the top fac

7、tor (3) met at the end of zero, a digital alignment factor and zero front (4) from a date, followed by a number multiplied by each digit number (5) that carryC and estimation(1) find two factor adjacent to the entire ten (2) are adjacent to the entire ten multiplied by a factor (3) the scope of the

8、result is estimated5, two digit, three digit, except by one digitA, dividend, divisor 二 business RemainderB and spin off calculationTwo digits: two digits according to the divisor, will be split into multiples of the whole divisor and the residual number ten, respectively divided by the value of the

9、 two, taking the sum ofThree digit: according to the dividend, will split into three digit whole hundred divisor multiples, then the rest of the digital split into multiples of the entire divisor and the residual number ten, respectively, three divided by the number of divisors, the three operators

10、togetherIf the whole hundred cannot be split into divisor multiples, then directly split into multiples of the entire divisor and the residual number tenC, the vertical calculation (business, multiplication, subtraction, fall)(1) from the highest point of the divisor, dividing (2) to which of the di

11、visors is to be listed(3) the quotient 1 is occupied by 0 (4), and the remainder is smaller than the divisor(5) check: quotient * divisor + remainder 二 divisor (6), pay attention to the end of divisor and zero in the middleD (estimation of quotient range)To find the divisor is closest to the two who

12、le ten, and the two numbers are multiples of the divisorThen divide the two numbers by the divisor, and the two quotient is the estimate in this formulaOr, to find than the divisor is small, and the whole is the divisor multiples of ten, the number is divided by a divisor, the business scope is smal

13、l and the number, the number range in big plus 10.Third unit1, the pronunciation of the decimal pointThe part of the integer is read by the original number The decimal part after the decimal point is to read out the numbers on each bit in turn (note the zero pronunciation) and refer to the book p342

14、 yuan cents(1) the integer part represents a few dollars, the first bit after the decimal point represents several angles, and the second bit after the decimal point indicates a fraction(2) show a few dollars and a few cents in decimal form (3), 1 yuan =10 angle, 1 jiao =10, 1 yuan 二100 cents3. The

15、decimal representation of kilogram and gram(1) 1 kg =1000 grams, the integer part represents kg, the first part of the decimal means hundreds of grams, the second represents a few grams, and the third represents a few grams(2) case1. 584kg二()G first think lkg584g, think lkg=1000g, then 1000+584二1584

16、, so 1. 584kg=1584g0. 070kg二()g wants second decimal places after the decimal point, and there is no number in the integer part, so0.070kg=70g3500g二()kg first divides 3500 into 3000g and 500g, and then 3000萨3kg writes 500g on the left of the decimal point, and lkg writes the decimal point to the rig

17、ht, so 3500萨3 500kg4. The decimal representation of kilometer and metre1 km 二 1000 meters (conversion method with kg / gram conversion)5, to solve different routesObserve several routes from the beginning to the point, then observe how many routes from this point to the finish line, and then go out

18、of the different routes in turn Calculate the shortest distanceA decimal representation of 6 meters and centimeters(1) lm=100cm(2) the integer part expressed several m, expressed dissatisfaction with the decimal number lm, name1y umptyumpth cm, decimal point right first said dozens of CM, second bit

19、 decimal point right said several cm(3) example: 3. 67m= () cm integer part 3 represents 3M, 3m=300cm, and decimal part represents 67cm300+67二367cm, so 3. 67m二367cm0. 8m二()cm first look at the integer part of 0, less than lm, the decimal part of 8 written at the decimal point after the first, indica

20、ting 80cm, second on the 0 omitted to write, so 0. 8m=80cm5cm二()m wants several cm to write second decimal places, and other places write 0 placeholder, so 5cm二0.05m 7 units of length (1) a unit of length between the inlet rate please reference books p42 green box (2) DM 1dm二10cm& date(1) 12 months

21、a year (left fist memory)The big 7, 31 days (January, March, May, July, August, October, December)I have 4 30 days (April, June, September, November)February is not large nor the moon, is a special month, there are 28 days, 29 days in a leap yearThere are 365 days, 366 days in a leap year(2) judgmen

22、t of the year of Ping and JirT;Four years a leap, a hundred years does not run, four hundred years and intercalatedThe year divided by 4, the remainder is not a leap year year divided by 4, the remainder is a leap yearWhen is the entire 100 to year, divided by 400, the remainder is not a leap year,

23、there is a remainder(1600, 2000, 2400) is a leap year(2) 7 days a week there are 52 weeks a year of more than 1 years52 weeks a year more than 2 days(3) first half, second half, quarter, etcFourth unit1, triangle(1) the triangle is divided into equilateral triangle, isosceles triangle and equilatera

24、l triangle by the edge(2) a triangle with two equal sides is called isosceles triangleA tri a ngle whose three sides are equal is called an equila teral triangle, also called a equilateral triangle(3) isosceles triangle including equilateral triangle An equilateral triangle must be an isosceles tria

25、ngle An isosceles triangle is not necessarily an equilateral triangle(4) isosceles triangle has a symmetrical axis An equilateral triangle has three symmetrical axes.2, area3. The size of a plane is called area4. The area of a rectangular square (1) the length of the square is lcm, the area is 1 squ

26、arecentimeters, and the writing is lcm2(2) rectangular area 二 length * width;S long 二a * B(3) square area 二 side length * side lengthS is =3 * a(note that the area is cm2, and M2 is not a unit of length)5 square metersThe length of the square is lm, the area is 1 square meters, and the writing is 1

27、m2In life, larger objects are square metersFifth unitExercise 1, multiplication and division calculation2, according to the division formula, compare the size(1) the divisor is equal and the divisor is large; the quotient is small(2) the divisor is equal and the quotient is large when the divisor is

28、 equal(3) the divide nd and divisor are not the same, calculate the size3, a few times a few times Duojiji problems (city lights before two P60-61)(1) will be judged according to the line graphNote: what is on the line graph?Is it a solid line or a dashed line?(2) first find a multiple, then multipl

29、y it several times, plus more (or less) numbers(3) if you use step-by-step calculation, you can write the answer directlyIf the column synthesis algorithm is written in the form of a recursive equation4 times, and the bad times, the problem (after two p6162 lights)Distinguish between 1 multiples or

30、multiples, several times after the summation, and 1 multiples add or subtractThe two method, the first is calculated according to the condition, and then the two part is added (or subtracted)The second first calculates the sum of the parts (or the differenee in the number of copies), and then multip

31、lies the number of each(1) take book p61/3 as an example and two methodsFirst, ask for the number of lotus bulbs, and then add the number of the rabbit lights to get a fewMake a synthetic formula 25 * 3+25Method two take rabbit lamp as 1 parts, lotus lamp as such 3, total 1+3=4Multiply again, each o

32、ne is the 25 lightMake a synthetic equation (1+3) * 25 note that parentheses don，t leak(2) take book p62/4 as an example and two methodsFirst, count the number of spherical bulbs, then subtract the number of the lamp of the rabbit，s lamp, and get a few moreMake a synthetic formula of 25 * 4 - 25Method two take the rabbit light as 1 parts, and the spherical lamp is considered as 4 of these, in total 4 - 1=3Multiply again, each one