How to expand squared brackets?

Take, for example, the bracket (a+5)^2. The longer way to do it would be to write (a+5)^2 as (a+5)(a+5) and multiply out that way. However, there is a shorter way where all you have to do is square the first term, square the last term and multiply their product by 2. Therefore, (a+5)^2= a^2 + 10a + 25

DC

Related Maths A Level answers

All answers ▸

Express 9^(3x+1) in the form 3^y, giving "y" in the form "ax+b" where "a" and "b" are constants.


A quantity N is increasing with respect to time, t. It is increasing in such a way that N = ae^(bt) where a and b are constants. Given when t = 0, N = 20, and t = 8, N = 60, find the value: of a and b, and of dN/dt when t = 12


Integrate, by parts, y=xln(x),


State the interval for which sin x is a decreasing function for 0⁰ ≤ x ≤ 360⁰.