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Number TheoryQuestion and Answers: Page 10 |
Prove : (n,7) = 1 → 7∣(n^6 − 1) |
can anybody do me a faver and tell me what the direct proof of mobius inversion formula is? (proof without using Dirichlet convolutions)? |
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Evaluate Σ_(k = 1) ^n ((4k+(√(4k^2 −1)))/( (√(2k−1)) + (√(2k+1)))) ? |
Determine all primes p for which the system of equations { ((p +1 = 2x^2 )),((p^2 +1=2y^2 )) :} ; has solution in integers x, y. |
Find all integral solutions to the equation (x^2 +1)(y^2 +1)+2(x−y)(1−xy)=4(1+xy) |
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A man has a wife with six children and his total income is Gh$8500.He was allowed the following free tax personal:......$1200 wife:...........$300 each child:.....$250 for a maximum of 4 dependant relative:$400 insurance:........$250 Taxed: the first $2000 at 10% the next $2000 at 15% the next $2000 at 20% the next $2000 at 25% calculate a)his tax free income b)his income tax c)his monthly income d)his net monthly income |
Show for the equation a^n = b^2 −1 where n>1 and a>2 are any natural numbers , there are no positive integer solutions for a and b ? |
f(x+2)+f(x−2)=f(x) f(1)=1 ,f(2)=2,f(3)=3,f(4)=4 then f(100)=? |
Given a = 1+3+3^2 +3^3 +3^4 +...+3^(100) Find the remainder of dividing the number by 5 . (a) 2 (b) 0 (c)4 (d)1 (e) 3 |
Let x,y,z be nonnegative real numbers, which satisfy x+y+z=1 Find minimum value of Q=(√(2−x)) + (√(2−y)) + (√(2−z)) . |
Suppose that the greatest common divisor of the positive integers a,b and c is 1 and ((ab)/(a−b)) = c . Prove that a−b is a perfect square |
Find gcd of x^4 +x^3 −4x^2 +x+5 and x^3 +x^2 −9x−9 |
Why the Fermat formula about prime numbers is for n = 5 and n = 6 fail? f(n) = 2^2^n + 1 |
8(1+(1/2))(1+(1/2^2 ))(1+(1/2^4 ))(1+(1/2^8 ))...(1+(1/2^(32) ))+ (1/2^(60) )=? |
Find the sum of the prime factors of 20^5 +21. |
Prove that 𝛑 is an irrational number |
Determine all functions f:R→R such that the equality f([x] y)= f(x) [f(y) ] holds for all x,y ∈R . Here by [x] we denote the greatest integer not exceeding x. |
Find the units digit of 2013^1 +2013^2 +2013^3 +...+2013^(2013) |
If x is a complex number satisfying x^2 +x+1 = 0 , what is the value of x^(53) +x^(52) +x^(51) +x^(50) +x^(49) ? |
How many positive integral solutions does 3x+5y=300 have? |
what the value of log _(10) (−1) in complex number |
Let S ={1,2,3,4,...,48,49} .What is the maximum value of n such that it is possible to select n numbers from S and arrange them in a circle in such a way that the product of any two adjacent numbers in the circle is less than 100? |
what the cooefficient of x^(10) from (1+x)×(1+2x^2 )×(1+3x^3 )×...×(1+2020x^(2020) ) |
If a and b positive real number where a^(505) + b^(505) = 1, then minimum value a^(2020) + b^(2020) is __ |