kiniki
Member
ok so im doing some past HSC papers for 2U maths and i came across these two questions and they totally stumped me, i looked at them and didn't even know where to start!!
first one is
Q1 a) Consider the geometric series 1 - tan^2 θ + tan^4 θ ...
i) when the limiting sums exists, find its value in simplest form
(ok so the limiting sum formula is S∞ = a/1-r yeah? a = 1 and how the fuck do i find the ratio ??? this question totally throws me and i know that its heaps similiar to what alot of questions will be like in the actual HSC so im stressing! is the ratio between the thingies, tan^2? or does it have something to do with trig identities and the ASTC?)
ii) for what values of θ in the interval -π/2 < θ < π/2 does the limiting sum of the series exist?
(so it does have something to do with ASTC?) ((WTF is this question??))
and the next question
Q2 a) Consider the function f(x) = loge x/x, for x > 0
i) show that the graph y = f(x) has a stationary point of x=e
(i started off with the quotient rule but HOW DO I DIFFERENTIATE A LOG? is it; y = loge x... y' = 1/x ? is that it? ive done nearly shit all on log laws :S)
(i don't get the wording of this question? not how to do the question but huh wait stop wut y=f(x)? am i making some really elementary maths error here?)
(x=e?? ive only dont stationary points where x = a number... e??? what is e?)
ii) dw about (ii)
iii) use the fact that the maximum value of f(x) occurs at x=e to deduce that e^x > (greater than or equal to) x^e for all x > 0
(im completely lost the moment it gets to deduce that rarara. even if i knew the turning points in (i) and graphs whatvs i would have nooo idea with this question)
And i went to my teacher about this today, and shes like dw i only gave you this to show you how hard its going to be.
how hard its going to be in 9 months??? i dont know how to do half the questions in these hsc papers because i havent learnt them yet ARRGHHH what the hell??? and im going to be doing the HSC for it in 9 months? is she crazy!
help
first one is
Q1 a) Consider the geometric series 1 - tan^2 θ + tan^4 θ ...
i) when the limiting sums exists, find its value in simplest form
(ok so the limiting sum formula is S∞ = a/1-r yeah? a = 1 and how the fuck do i find the ratio ??? this question totally throws me and i know that its heaps similiar to what alot of questions will be like in the actual HSC so im stressing! is the ratio between the thingies, tan^2? or does it have something to do with trig identities and the ASTC?)
ii) for what values of θ in the interval -π/2 < θ < π/2 does the limiting sum of the series exist?
(so it does have something to do with ASTC?) ((WTF is this question??))
and the next question
Q2 a) Consider the function f(x) = loge x/x, for x > 0
i) show that the graph y = f(x) has a stationary point of x=e
(i started off with the quotient rule but HOW DO I DIFFERENTIATE A LOG? is it; y = loge x... y' = 1/x ? is that it? ive done nearly shit all on log laws :S)
(i don't get the wording of this question? not how to do the question but huh wait stop wut y=f(x)? am i making some really elementary maths error here?)
(x=e?? ive only dont stationary points where x = a number... e??? what is e?)
ii) dw about (ii)
iii) use the fact that the maximum value of f(x) occurs at x=e to deduce that e^x > (greater than or equal to) x^e for all x > 0
(im completely lost the moment it gets to deduce that rarara. even if i knew the turning points in (i) and graphs whatvs i would have nooo idea with this question)
And i went to my teacher about this today, and shes like dw i only gave you this to show you how hard its going to be.
how hard its going to be in 9 months??? i dont know how to do half the questions in these hsc papers because i havent learnt them yet ARRGHHH what the hell??? and im going to be doing the HSC for it in 9 months? is she crazy!
help