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How do you prove that (3^n)-1 is always a multiple of 2?

Proof by Induction: The method of Proof by Induction is a simple but very powerful technique. It involves 3 steps: 1) Showing a claim is true for a basic integer value of n (e.g. 0 or 1) 2) Assuming the clai...
SA
Answered by Saleem A. • Maths tutor
19918 Views

How do you add or subtract complex numbers?

A complex number has the form a+bi. We call a the 'real' bit (ie. the bit on a regular number line) and b is the 'imaginary' bit. To add or subtract complex numbers you just add the real bits of both togethe...
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Answered by Chloe B. • Maths tutor
6099 Views

How to sum an arithmetic progression?

Whilst it is very easy to just plug the numbers into the formula you are given on your formula sheet there is a much faster and more intuitive method of doing this. If we have n numbers beginning at a with a...
VP
Answered by Vandan P. • Maths tutor
6495 Views

The price of a TV is reduced in a sale by 30%. If the sale price is £280 what was the original price?

A question from 13 + specimen paper. After the price of TV is reduced 30 % the price is £280. This means that £280 is 70% of the original price. Therefore if you make an equation 280 x 100 / 70 you will get ...
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Answered by Taeseong K. • Maths tutor
18200 Views

Expand (2x-3)(4x+4) using the FOIL method.

Question: Expand (2x-3)(4x+4) We will be using the FOIL method. FOIL is an ancronym: F=first O=outside I=inside L=last So, to begin, we start with the first term in each bracket, and multiply them together. ...
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Answered by Miriam W. • Maths tutor
10826 Views