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Find the values of x given the equation (4x^2)-3x+1=2 using the quadratic formula.

4x 2 -3x+1=2The first step is to rearrange the equation, equating it to zero: 4x 2 -3x+1-2=0 which gives 4x 2 -3x-1=0. Next we apply the quadratic formula: x=(-b +/- sqrt(b 2 -4ac))/2a where a=4, b=-3 and c=...
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Answered by Shahnaan M. • Maths tutor
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25cm3 NaOH was titrated with 0.05mol dm-3 HCl. 21.5m3 of HCl neutralised 25cm3 of NaOH. What is the concentration of NaOH in mol dm-3?

NaOH + HCl --> NaCl + H 2 O 1 : 1 : 1 moles (mol) = concentration (mol dm -3 ) x volume (dm 3 ) n(HCl) = 0.05 (mol dm -3 ) x 21.5/1000 (dm 3 ) = 0.001075 moles (1.075 x 10 -3 ) Using 1:1 molar ratio: n(Na...
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Answered by Britta A. • Chemistry tutor
6012 Views

Describe the adaptations for efficient gas exchange in the lungs?

For efficient diffusion there must be a concentration gradient that is maintained, a large surface area to volume ration and a short distance for the gases to diffuse across. There are adaptations at the sit...
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Answered by Isla M. • Biology tutor
8183 Views

Time, T, is measured in tenths of a second with respect to distance x, is given by T(x)= 5(36+(x^2))^(1/2)+4(20-x). Find the value of x which minimises the time taken, hence calculate the minimum time.

To solve this problem we first must look into the given formula for time (T). It is stated, in the question, that the time taken is dependent on distance x. From this we can infer that the following problem ...
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Answered by Aziz H. • Maths tutor
4102 Views

Explain the different situations in which you would use ‘por’ and in which you would use ‘para’

Para: Tiempo futuro próximo (near future time): Tengo que terminar este trabajo para el día Opinión (opinion): Para mí, lo mejor de inglaterra es la educacion - Destinatario (to a person) : ¿Te gusta esta ca...
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Answered by Rachel S. • Spanish tutor
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