Materi Matematika Kelas 8: Pola Bilangan

Hi love On this occasion we

will discuss the 8th grade mathematics material

about number patterns

in this material we will discuss

how to determine the equation of

a number sequence Have you ever

seen a question like the one below there is a

question

0.2 point four point comma

semicolon semicolon 10 the figure

is a number pattern question Can you

guess the dots

the answer is 6 and 8 where did it

come from Who is it from

before we discuss it we

have to understand several things including

number stores and equations in a

number sequence

previously discussed regarding the example of

this number pattern question

0.24 point 6 point 8 point 10 the number term

is where the number is located

pay attention to the explanation below zero

is the first term 2 typical the

24th term is the 36th term is the

48th term there is the 5th term and 10 is the

6th term how do you understand my sweet

number

Well now determining the equation

determining the equation a

number sequence is actually difficult but easy

admin often says that because we are

creative and careful in seeing a

number sequence pay attention to the example

below there is zero point two point four point comma semicolon

semicolon

10 number patterns above we

using the formula x + 2 will be

obtained from the known term

minus the previous term so we can

calculate from the second term fried the

first term is two minus 02

next is four minus two is

also equal to the second the 3rd term

minus enough second

based on the previous shadow above it

can be concluded that the next number is

definitely plus two so 4 plus the

next two numbers is six and

both are eight as the

next step to test Is it true or

not we just add it by lifting the

last two dots 8 plus 2

the result is ten then the

complete number pattern will be 0.2

point four point 6 point 8 point 10 we

see the last term is 10 then

the equation x + 2 is correct

Let's try the next example there is a

question here 1.4 point seven point semicolon

semicolon 16 point dot

still using the same method that is the

known term minus the

previous term in this case the second term and the

first term are known then we subtract

that first 4 minus 1 = 3 now We test

for the next term that is the 3rd term

minus the 27th term minus 41 also =

3 based on the above it is found

that the next number is definitely plus +

3G

Hi

no then the dots we can fill

with seven plus 3 = 1010 plus

three more salonan 1313 plus three

more = 16 and 16 + 3 = 19 as

the last then the complete answer is

1.4 point seven point 10 point 13 point 16

point 19 easy right

next we will understand about

Fibonacci numbers

babla you find a pattern like

below for example is 0.1 point 1.2

point three point five point eight and so on the

pattern is called the

Fibonacci number sequence

What is the Fibonacci number sequence is a

sequence Where the 3rd term is obtained

from the sum of the first term and the second term

in the example above is zero plus

1 the result must be one as the

next 3rd term the 4th term is

obtained from the sum of the 2nd term and the

third term namely you plus 1 the result is

the same as tua which becomes the 4th term the

fifth term is obtained from the sum of the

3rd term and the 4th term namely one + 2 = 3

now this three becomes the 5th term and

so on so Can

you guess the

next number after the 8th Yes the

next number consecutively is 13 that is the

result of 5 plus

821 from eight plus 13 and 34 from

13 plus 21 remember in

Fibonacci numbers it is enough to add the two

previous terms

have understood the basics of number patterns

then we will continue the material

next there are two objects that we discuss

namely the pattern of the sequence of triangular numbers and the

pattern of the sequence of square numbers if

a question forms a pattern either

triangular or square then the

colon formula will apply Let's discuss one

by one starting

Hi now

next Pay attention to the picture below

we can see that there are two colors

there namely red and blue if we

pay attention to each ball whether red

or so it forms a triangle

the picture is an example of a

triangular number pattern

What if we have to determine

the number of blue balls in the

100th pattern in solving such a problem

then the formula UN = half

times n times in brackets N + 1 applies and the

UN description is the term

asked hand and n is a sufficient number well

next there is an example of a question here

determine the number of blue balls

in the 100th pattern based on the picture

beside then the solution is

we first write the formula UN

UN = half

Indonesia times n times the opening bracket n

plus one closed parenthesis now each

n we replace with the number 100 because

remember n is the term in question

or the pattern in question then we

replace the UN with

u100

= half

times n remember replaced with 100 100

times the open parenthesis 100 plus

12 with 100 we can do this

remember we can do it with the

strikethrough system the condition system is to divide

these two numbers by the same number two

It can be divided by two

likewise 100 can be divided by two market

sacoret

we cross out both divided by 22 divided by

two is one 100 divided by two is 50

Indonesia next then

u102 = 1 times 50 which is 50

times 100 plus one which is 101 then

the answer of u100 is

5050 based on 50011 finally 5050

so the number of blue balls in the

100th pattern is 5050 how easy is it

simple just What is the formula and

just enter the number asked

by the

next porn is the square number pattern

on The square number pattern

is a development of the

previous pattern. Look at the picture below.

There are the 10th pattern, the second pattern, the third pattern, and the

fourth pattern.

If you find a pattern like the one above, the

formula UN = 2 times n minus one applies.

For example, determine the number of balls

in the 15th pattern. Based on the

following picture, the solution is to

first enter the UN formula for the

square number pattern. UN = 2

times n minus one, then

UN. This is replaced with 15

= 2 times each harvest is replaced with

15. 15 minus

porn, then

15.00 is the same as two times 15 is

30 minus one, then u-15 will

be

29,

so the number of balls in the 15th pattern

is 29. That's it. Now,

what is the square shape of the

square number pattern when asked for the

number of terms n. Look at the picture

below. The balls are added together and

can be rearranged into a

square shape as follows.

The formula for determining the number of terms n

in a square number is sn = n

squared.

Let's immediately discuss the example of the problem. It's a

headache if we know the pattern of the square number sequence is

1.3

five point seven point dot. Now, what is

asked is to determine the number of

terms to 20, then we Enter the formula

first, the formula is to

ask for the number of magnets, enter the formula SN

sn = n squared,

all the easier ones we replace with the one

asked, namely 20, then it is written S20

= 20, strengthened, meaning S20 will

be 20 times

25

ks20 is

456, it is easy to find the amount of

power, maybe for this time that's enough,

thank you for watching this

learning video, this is the end, hopefully it will be

useful for all of us, don't forget to

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