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Find the area under the curve y=xexp(-x)

first recognise ‘area under’ = integrationfunction is a product so by partsset x=u; exp(-x)=dv/dx integral(udv/dx)=uv-integral(vdu/dx)
du/dx =1; v=-exp(-x)ans=(x.-exp(-x))-integral(1.exp(-x)dx)ans=-x...

Answered by • Maths tutor

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What is the difference between RAM & ROM and the ways they are used within a computer system?

In a computer system, RAM is used to temporarily hold programs & data while they are required by the CPU. Storing them in RAM, due to its rapid access times and close proximity to the CPU, means its c...

Answered by Sam P. • Computing tutor

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Using z=cos(θ)+isin(θ), find expressions for z^n-1/z^n and z^n+1/z^n

We make use of De Moivre's Theorem which states that (cos(θ)+isin(θ))^n=cos(nθ)+isin(nθ).z^n-1/z^n=cos(nθ)+ isin(nθ)-cos(-nθ)- isin(-nθ)=cos(nθ)+ isin(nθ)-cos(nθ)+ isin(nθ) (by trig relat...

Answered by Bogosi S. • Further Mathematics tutor

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Explain 2 Advantages of Using Die Casting over Sand casting for the manufacturing of a Metal Engine Block.

Options: (1 mark for 1 Advantage, 1 mark for 1 Explanation)Die casting has a better surface finish (1 mark). This Allows for a reduction of additional processes needed to finish the product which can make...

Answered by Ben S. • Design & Technology tutor

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