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How do I differentiate an algebraic expression? (e.g. y=3x^4 - 8x^3 - 3) [the ^ represents x being raised to a power]

y=3x 4 -8x 3 -3 Let's say we want to calculate dy/dx. For a term A x n , the differential with respect to x is An x n-1 . For a constant value, we can say that n=0 because x 0 =1. This means that when you di...
PC
Answered by Patrick C. • Maths tutor
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Work out the nth term of the sequence 3, 7, 11, 15, ...

This is an example of an arithmetic series because each term is +4 from the previous term.This means for the "nth term" we start with +4n.Now we take a specific term from the sequence e.g. 3 (1st t...
AL
Answered by Alice L. • Maths tutor
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How do I expand double brackets? E.g. (4x+7)(3x+5)

In order to expand the brackets, we need to ensure that EVERYTHING in the left bracket is multiplied by EVERYTHING in the right bracket. There are 3 methods for helping us to times out the brackets. These ar...
SA
Answered by Shona A. • Maths tutor
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Elemental analysis of a carbohydrate X showed the sample contained 48.7 % carbon and 8.1 % hydrogen by mass. Find the empirical formula of X.

These sorts of questions can look difficult, but if you learn the steps needed to solve them then they are all very similar. Step 1: Since we are told that X is a carbohydrate, we know that the only other co...
JB
Answered by Jack B. • Chemistry tutor
2153 Views

2NaNO3 --> 2NaNO2 + O2. When a sample of solid sodium nitrate was heated 96cm3 of gas was collected, calculate the mass of NaNO3 Decomposed

We know that the reaction is a 2:1 ratio as 2 moles of NaNO3 is used to form 1 mole of O2 so first we need to find the moles of the product produced SoVolume of gas (dm3)= number of moles x 24dm3Therefore vo...
SZ
Answered by Sara Z. • Chemistry tutor
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