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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
3181 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 = ...
BK
Answered by Brandon K. • Maths tutor
7962 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
7186 Views

A square is placed in a circle of area (49π)cm^2 such that all four vertices of the square lie on the circumference of the circle. What is the area of the square?

It's always helpful to draw a diagram beforehand.Since we know the area of the circle is (49π)cm 2 , we can work out the radius using A=πr 2 . Rearranging, we get r = 7cm. Add this information to our diagram...
KS
Answered by Karnan S. • Maths tutor
5549 Views

Make x the subject of the formula y=(4x+5)/x

xy=4x+5 xy-4x=5x(y-4)=5x=5/(y-4)
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Answered by R P. • Maths tutor
5396 Views