Search over 10,000 free study notes

(2n + 1) ² - (2n-1)can also be written be as (2n +1)(2n + 1) - (2n-1) Two brackets next to each other indicate that you must multiple them by each other, this is also known as expanding the bra...

Firstly we identify the problem, in this case we have 2 equations which contain a total of 2 unknowns, it is therefore simultaneous equations.Our first step is to rearrange an equation of our choice to gi...

There are three trigonometric ratios: sine, cosine and tangent, shortened to sin, cos and tan. Firstly, let's draw a triangle and label the sides. In a right-angled triangle, we call the bottom side betwe...

First, we need to work out the difference (increase) between our two numbers:420 - 30 = 390
Second, we divide the difference by the original starting number:390 / 30 = 13
Lastly, we multiply thi...

To factorise a quadratic in the form ax^2+bx+c we need to find 2 numbers which add to get b and multiply to get c. In this case a=1, b=1 and c=-12. Two numbers which add to 1 and multiply to -12 are 4 and...