Recent content by Maatttt0

Aha yay! Thank you Unit - muchly appreciated :D

Hey guys, Thank you for both of the replies :) micromass; I'm didn't think it was n+1 :S my formula booklet just has n by itself. Unit; I got the answer to come out I think xD 3^{h} * \frac{S}{h} = 3^{h} + 3^{2h} + ... + 3^{nh} 3^{h} * \frac{S}{h} = (3^{h}(1-3^{1})) / (1-3^{h})...

Homework Statement This isn't the whole question, I understand the prior parts but somehow stuck on the "easy" part :( Need to solve a geometric progession problem.. find the sum of: h(1 + 3^h + 3^2h + ... + 3^(n-1)h) Where nh = 1 The sum should equal to (2h)/((3^h) -1) which is...

Ahh got it thank you Integrate the dA/dt to get πr^2 and work out r by equating it to the 1900 then sub the r back into the dr/dt, thanks

Homework Statement Leaking oil is forming a circular patch on the surface of the sea. The area of the patch is increasing at a rate of 250 square metres per hour. Find the rate at which the radius of the patch is increasing at the instant when the area of the patch is 1900 square metres...

Thanks for the input to both of you :) I understand now thanks, HallsOfIvy :smile: woo!

Homework Statement Given that: f(x) = 2(1-x) for 0 < x < k ...0 for otherwise sketch the graph of f(x) and find: (i) the value of k, (ii) the median of x Homework Equations The Attempt at a Solution (i) I sketched the graph and got a line from (0,2) to...

Oo okay, thank you - just thought it was wrong considering the grad was 64 that's all. Thanks Susanne for checking :D

Thank you for your reply, Susanne, it's just that I've never seen the tangent formula before :S Also my homework is based around the idea of differentiating so I was wondering if I was going in the right direction :S

Homework Statement Find the equation of the tangent to the curve y = x2(x + 1)4 at the point P(1,16) Homework Equations The Attempt at a Solution dy/dx x2(x + 1)4 = (x + 1)3((x + 1)2x + 4x2) = (x + 1)3(6x2 + 2x) = (x + 1)3(2x)(3x + 1) Subst. 1 into find grad. (1 +...

Thank you for the help JeSuisConf but I've spotted the error.. Silly me, was making it far complicated than it actually is.. Thank you for looking though :smile:

Homework Statement Given that cos C = 12/13 where C is a reflex and sin D = 3/5 where D is acute, find the exact value of cos ( C + D ). Homework Equations The Attempt at a Solution I used the Addition Formulae: cos(A+B) = cosAcosB-sinAsinB cos(12/13)cos(2/5) -...

Ahh I understand it now - just these ln's cofusing me! Well thank you very much danago for your help :D

Hmm.. I must be confusing myself with something else :\ I'm following you so far (even though there's not much to follow lol). Okay, I'm unsure how to work b :S

If you put 1/2 into 1/x you get 2.. so the tangent's gradient will be -2 The logarithm's are really getting to me.. :/