Ages Tuan ' s father = mn

Father's years of birth = pqzy

We have

\(mn\div2=p+q+z+y\)

\(a\times10\div2+b\div2=p+q+z+y\)

\(a\times5=b\times2\)

\(\Rightarrow a=2;b=5\)
So father age is 25

Father's age in 2019 is:

       \(25\times2=50\left(ages\right)\)

Father year of birth is :

     \(2019-50=1969\left(years\right)\)

So year of birth is 1969

Lê Quốc Trần Anh is all

Thank you

Let n be the number of sides of the regular polygon \(\left(n\in N;n>2\right)\)

We have : \(\dfrac{180\left(n-2\right)}{n}=144\Leftrightarrow180n-360=144n\)

\(\Leftrightarrow180n-144n=360\Leftrightarrow36n=360\Leftrightarrow n=10\)

So, the regular polygon has 10 sides

Call the number: abcd.

We have: 

+ \(a=1;2;3;4;5;6\)  

+ \(b=2;3;4;5;6;7\)

+ \(c=3;4;5;6;7;8\)

+\(d=4;5;6;7;8;9\)

So then there are: \(6.6.6.6=1296\left(numbers\right)\)

ANSWER: 1296 numbers

Next 2 years,the sum of Madison's age and 3 times Harper's age is:

       47+2+2 x 3=55(ages)

Put the  Madison's ages is :a

Put the Harper's ages is:b

We have:a+3b=55\(\Rightarrow\)5b=55\(\Rightarrow\)b=11

So the Harper's age is 11 ages

Tell the age of Madison and Harper sequence is a and b

\(\Rightarrow\left\{{}\begin{matrix}a+3a=47\\\dfrac{a+2}{b+2}=2\end{matrix}\right.\)

=> a + 2 = 2b + 4

=> a = 2b + 2

=> a + 3b = 2b + 2 + 3b = 47

=> 5b = 45 

=> b = 9

=> a = 47 - 3.9 = 20

So the age of Harper is 9

a, b, c, d \(\ne\)0

a,b,c,d=1

 \(\dfrac{a+b+c}{a}+\dfrac{a+b+c}{b}+\dfrac{a+b+c}{c}\)

\(=\dfrac{1+1+1}{1}+\dfrac{1+1+1}{1}+\dfrac{1+1+1}{1}=3\)

\(\Rightarrow A=\dfrac{1}{1+1+1}+\dfrac{1}{1+1+1}+\dfrac{1}{1+1+1}+\dfrac{1}{1+1+1}=\dfrac{1}{3}\times4=\dfrac{4}{3}\)

Where is "d"?

Q = 1 . 3 . 5 . 17 . 257 + 1

=(2 - 1)(2+1)(2² + 1)(2⁴ + 1)(2⁸ + 1) + 1

=(2² - 1)(2² + 1)(2⁴ + 1)(2⁸ + 1) + 1

=(2⁴ - 1)(2⁴ + 1)(2⁸ + 1) + 1

=(2⁸ - 1)(2⁸ + 1) + 1

=(2¹⁶ - 1) + 1

=2¹⁶

Q = 1 . 3 . 5 . 17 . 257 + 1

=(2 - 1)(2+1)(22 + 1)(24 + 1)(28 + 1) + 1

=(22 - 1)(22 + 1)(24 + 1)(28 + 1) + 1

=(24 - 1)(24 + 1)(28 + 1) + 1

=(28 - 1)(28 + 1) + 1

=(216 - 1) + 1

=216

Bạn là người copy câu trả lời của mình

Put A = 1.2 + 2.3 + 3.4 + ....... + 199.200

 => 3A = 1.2.3 - 1.2.3 + 2.3.4 - 2.3.4 + ....... + 199.200.201

=> 3A = 199.200.201

=> A = 199.200.201/3

=> A = 2666600

Land A = 1.2 + 2.3 + 3.4 + ....... + 199.200

 => 3A = 1.2.3 - 1.2.3 + 2.3.4 - 2.3.4 + ....... + 199.200.201

=> 3A = 199.200.201

=> A = 199.200.201/3

=> A = 2666600

Put A = 1.2 + 2.3 + 3.4 + ....... + 199.200

 => 3A = 1.2.3 - 1.2.3 + 2.3.4 - 2.3.4 + ....... + 199.200.201

=> 3A = 199.200.201

=> A = 199.200.201/3

=> A = 2666600