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Prove that the square of an odd number is always 1 more than a multiple of 4

2n+1 will always be an odd number (e.g. if n is equal to 3 the answer would be 7, an odd number) So, we square 2n+1 and write this as (2n+1)² 2n +12n 4n...

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A sequence is defined as: U(n+1) = 1/U(n) where U(1)=2/3. Find the sum from r=(1-100) for U(r)

U_n+1=1/U_n where U₁= 2/3First of all, we need to find U₂ and U₃ and so on, up until we notice a pattern in the answers. U₂ = 1/(2/3) = 3/2U...

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Find the indefinite integral of f(x)=(1-x^2)/(1+x^2)

Int() in this case will refer to integralsAnswer is: f(x)=(1-x^2)/(1+x^2)=(2-(1+x^2)/(1+x^2)=-1+2/(1+x^2)=> Int(f(x))=Int(-1+2/(1+x^2))=Int(-1)+2Int(1/(1+x^2))=-x+2tan^-1(x)+C

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There are 495 coins in a bottle. 1/3 of the coins are £1 coins. 124 of the coins are 50p coins. The rest of the coins are 20p coins. Work out the total value of the 495 coins

495/3 = 165 => £165 worth of £1 coins
124 x 0.5 = 62 => £62 worth of 50p coins
We know the number of coins that are NOT 20p coins. Therefore, we can subt...

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