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Whoops, made a mistake when I was looking at the answers, so I thought the solution was 2pi/3. Geez, I can't even read the answers correctly. :rolleyes:

Yes, that's right. Thanks. Time for another; In the diagram, the line l1 has equation 2x - 3y + 5 = 0 and the line l2 passes through the points P(0, 6) and Q (4, 0). Find the area of the triangle RSQ.

Has anyone got an answer to the question? I'm still stuck... :(

Having trouble with this question, can anyone show me the best way to tackle it? It asks; On a number plane, the points P, Q and R have coordinates of (3, 0), (0, 2) and (6, 4) respectively. Find the shortest distance from the point R to the line PQ. Do I simply find the equation of the line...

Okay, thanks very much. :) EDIT: BTW, the answer is 2pi/5, if you were wondering.

D'oh! For some reason I was substituting y = 0 instead of x = 0. Thanks. :) EDIT: I think you may have made a mistake. Did you square x before integrating it?

Thanks, I can't believe I didn't see such a stupid mistake... Got time for one more? I'm stuck on the first part of this question; a) Find the points of intersection of the curve y = 2 + √(4x) with the y-axis and the line y = 4. The answers for this one should be y = 2 (y-axis) and x = 1...

ARG! Stuck on yet another question. I'm sure it's just because I'm entering the equation in to my calculator incorrectly, but I just can't get it. Can someone help me out? The question asks; Find the volume of the solid of revolution formed by rotating the curve y = x - 1/x about the x-axis...

Thanks guys, I'm gonna put this down to calculator troubles. I moved some of the brackets around and finally got the right answer. I'll have to be more careful in the future. :)

1 and 1/3 is the answer, I just can't seem to get it through my own working. Could you show me yours so I can see where I'm going wrong?

Okay, I've gone through this question several times and just can't seem to get the right answer. Can someone point out what I'm doing wrong? = Intercepts = x = 1 and x = 3 = 13∫(x2 - 5x + 5) - 13∫(-x + 2) = [(x3)/3 - (5x2)/2 + 5x]13 - [(-x2)/2 + 2x]13 = [((3)3)/3 - (5(3)2)/2 + 5(3) -...

Thanks, but there's a third part to the question I forgot to ask. It should be pretty straight-forward, but my working doesn't seem to be producing the right answer. c) Find the area of the region enclosed between the parabola and the line y = -x + 2.

No problem, have another :D; a) Prove that the line y = x - 4 is a tangent to the parabola y = x2 - 5x + 5. a) Let P be the point where the line y = x - 4 touches the parabola y - x2 - 5x + 5. Show that the normal to the parabola at P is y = - x + 2. The first part has me stumped...

Thanks. You didn't need to solve the first part though, I had that covered. ;)

Can anyone give me a bit of help with this integration question? The first part I can figure out but I don't know how to do the second. It asks; The points A (3, 9) and B (-2, 4) lie on the parabola y = x2. The line y = x + 6 joins A and B. The point P (p, p2) is a variable point on the parbola...

Thanks. And now, time for another; A piece of wire of length 5 meters is bent to form the hypotenuse and side of a right angled triangle ABC. Let the length of the side AB be x meters. What is the maximum possible area of the triangle? What I know so far; The hypotenuse (AC) = 5 - x BC = √(25...

Thanks again, here's another; A plane is to fly 3000km at a constant speed of v km/h. When flying at v km/h the plane consumes fuel at the rate of (50 + 10-6v3) litres per hour. a) Show that on a journey of 3000km at a speed of v km per hour, the expression for the total amount of fuel used, A...

Thanks for that, now time for another... A cylinder of radius r cm and height h cm is inscribed in a cone with base radius 3 cm and height 10 cm, as in the diagram. a) Show that the volume V of the cylinderis given by V = [10(pi)r2(3 - r)]/3 b) Hence find the values of r and h for the...

I'm having a bit of trouble with the second half of this question... And open rectangular box has four sides and a base, but no lid. The box has a base of dimensions 3x cm and 2x cm, and a height of y cm. a) Write dow formulae for the outer surface area A cm2 of the box and the volume V cm3. =...

I'm stuck on this particular simple harmonic motion question. I can do the first half, but the second has me baffled. Here it is; a) If x = a sin nt + b cos nt, find the acceleration of the particle in terms of t and show that a = -n2x. = v = an cos nt - bn sin nt = a = -an2 sin nt - bn2 cos...