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Find the interserction points of: The circle, x^2+(y-1)^2=18 and the line, y=x+1.

To solve this question, we have to use substitution. We substitute the line equation,y=x+1, into the circle equation so that we get, x^2 + (x+1-1)^2=18. This reduces to 2x^2 = 18, then dividing both sides by...
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Answered by Alex R. Maths tutor
3165 Views

integral of xe^-x dx

Using integration by parts by letting u=x and dv/dx=e^-x. this implies that du/dx=1 and v=-e^-xThe By Parts formulae is u.v - integral(v.du/dx) = -xe^-x - integral(-e^-x).1 dx = -xe^-x + integral(e^-x) dx = ...
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Answered by Brandon K. Maths tutor
7931 Views

How do you form the Perfect Tense? (passé composé)

The 'Perfect Tense' is made of two parts: The 'AUXILIARY' (form of avoir/ être) + the 'PAST PARTICIPLE' You pick the auxiliary according to the subject (ie. if you want to use 'nous' then the auxiliary will ...
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Answered by Isobel D. French tutor
2260 Views

Sean drives from Manchester to Gretna Green. He drives at an average speed of 50 mph for the first three hours. He then breaks and drives the final 150 miles at 30 mph. Sean thinks his average speed is 40 mph ,is he correct?

This is a relatively complicated mechanics question requiring the student to put aside their initial assumption and work with the actual meaning of average speed. In order to do this the student must find ou...
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Answered by Adam B. Maths tutor
7169 Views

Why did Communist Russia win the Russian Civil War?

When assessing this question, it is worth taking into account the natural resources and geographic factors which gave Lenin's government an inherent advantage. A good starting point for this is that the terr...
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Answered by Daniel R. History tutor
3389 Views