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When using cm3 as the unit for volume to calculate the concentration why must you divide the cm3 by 1000?

As I’m sure you already know, the units of concentration are mol dm -3 . So before we calculate concentrations we must convert the volume with units cm 3 to dm 3 . 1 dm is the equivalent of 10 cm . So, by cu...
HB
Answered by Hannah B. • Chemistry tutor
25694 Views

Solve the quadratic equation: x^2 - 2x - 15 = 0

We need to find numbers that multiply together to give -15. This could be -1 and 15, 1 and -15, -3 and 5, 3 and -5. The numbers we need must add up to -2 as well (from -2x term). Therefore our set must be 3 ...
SK
Answered by Sabrina K. • Maths tutor
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Factorise completely ( x − 4x^3)

(x-4x 3 ) = x(1-4x 2 ) Just taking a factor of x out of both terms Within the inner bracket we have a difference of two squares. 1 2 =1 and (2x) 2 =4x 2 therefore we can write x(1-4x 2 ) = x(1-2x)(1+2x)
EC
Answered by Edward C. • Maths tutor
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Y=3x^2-2 ( Make x the ubject of the formula

x=((y+2)/3)^1/2
TP
Answered by Talha P. • Maths tutor
4512 Views

find the values of x when 3x^2 - 6x - 9

First we will need to factorise the equation. Start with the 3x^2 term and notice 3 is prime so must have 3x and x terms. (3x - 9) (x + 1) or (3x + 3) (x - 3) Setting the brackets to 0 gives us 3x - 9 = 0 an...
DM
Answered by Dylan M. • Maths tutor
5396 Views