Hey,

I missed my maths lecture on friday when we had homework dished out, got it today instead. Its for tomorrow though.

Im pretty damn poor at maths (have to take 1st year Uni Maths though for my Comp Course) and havent done maths since 5th year of High School (2 Years ago) and I got a C in it. (lowest grade needed by Uni)

So basically I need a little help with these Q's

Calculus:

9.

(i) the point of intersection of the curves y = 1/x and y = 8x²

ive done part of that but got stuck here:

1/x = 8x²
1 = 8x(cubed)

(ii) the points of intersection of the parabola y = 1/2x² and the circle x² + y² = 80

Algebra:

17. Express each of the following as a single logarithm as simply as possible

(iv) 3loga(x²y) - 2loga(xy^5)


Yeah I know this might be very easy to some people but please understand english was my subject, never was all that great at maths

Thanks!

ps. Anyone have any websites I may find useful for maths? (Im currently waiting for the supplementary 1st Year Maths book to arrive that the Uni recommended. That will be of great help to me ... hurry up amazon )

I could draw them out and figure them, but i want to goto sleep now .

Try omnigraph pro (there should be a trial, google it). It let's you create these curves and solve them visually (visual graphs are never as accurate as algebraic ones, unless a computer is plotting them )

Ok I'll try a bit....
(i)
1 = 8x^3
Would then become 1/8 = x^3
Which is then... cuberoot(1/8)
Which is the same thing as cuberoot(1)/cuberoot(8)
Which is 1/2 because 2x2x2 = 8.
Final Answer 1/2.

The two graphs intersect at x=1/2.

Will work on the next one and post it.

If I am not mistaking, when you subtract logarithms with the same base then you divide them..

so I think the answer would be:

3loga(x²y)
------------
2loga(xy^5)

I hope i didn't make an asshat out of myself.


This website should help: http://www.purplemath.com/modules/logrules.htm (I can't read it right now.. too many probs)

Yeah, you did make and asshat of yourself.

yeah, wow.

3rd is quite simple, just use your basic laws of logarithm.

The answer is LOGa(x^4/y^7) I think

As for the 2nd question it should really be done with a graphical calculator (at least this was the case when I did the IB).

asshat.. haha j/k i dont know wtf.