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How to find the nth term of a quadratic sequence?

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. Now ...
SK
Answered by Sawan K. Maths tutor
7721 Views

What exactly causes the sounds heard by a stethoscope

There are 2 sounds heard by a stethoscope, the so called 'lub dub'. The lub being the closing of the atrioventricular valves (i.e. the valves between the atria and the ventricles). This is caused by an incre...
JL
Answered by John L. Biology tutor
5319 Views

Give the possible values of x when x^2 - 5x + 4 = 0

First, when faced with a question like this you must factorise the expression. So we need to factorise x 2 -5x+4 into 2 linear parts. (Linear terms are terms without any powers of x). To do this, we need to ...
SD
Answered by Sam D. Maths tutor
6308 Views

Explain why cell surface membranes are also called 'phospholipid bilayers'?

A cell surface membrane is made up of a type of molecules called phospholipids , so what is a phospholipid bilayer ? The first step would be to break down the term. ‘ Phospho ’ means that the molecule(s) mus...
JC
Answered by Jamie C. Biology tutor
10564 Views

Question: Expand (p + 2)(p - 5)

Expanding - or geting rid of brackets. Make sure you multiply everything by everything! Correct: p 2 +2p -5p -10 = p 2 -3p -10 Wrong: p 2 + 2p -5 ...forgot that the -5 also needs to be multiplied by (p+2) Wr...
AN
Answered by Abdul N. Maths tutor
12358 Views