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Find the difference between each term in the sequence. Then find the second difference, i.e. the difference between each of the primary differences. Divide this by 2, to give you the coefficient of n^2. N...

First, when faced with a question like this you must factorise the expression. So we need to factorise x²-5x+4 into 2 linear parts. (Linear terms are terms without any powers of x). To do this,...

Expanding - or geting rid of brackets. Make sure you multiply everything by everything! Correct: p² +2p -5p -10 = p² -3p -10     Wrong: p² + 2p -5 ...forgot that the -5 al...

Ratios are used to show how things are shared. A ratio of 7:5 means that for every 7 red sweets there are 5 blue sweets.
Step 1 - 7 + 5 = 12 This means there are 12 parts to the ratio
Step 2 -...

There are 8 beads in total; 3 out of 8 are black; 5 out of 8 are white.
When the first bead is taken, there is a 3/8 chance of the bead being black, since 3 out of the 8 beads are black.
Since t...