Inequalities Area questions (1 Viewer)

[clintmyster]

Imageshack - img0002ox
Imageshack - img0001mu

For the first link, can someone please do the question for me because im like clueless. Also, anything that looks like a k is actually a h. so its like 6h or 7&h.

With the second link, for cii) is my teachers working out actually right because hes only considering n terms yet his geometric series is n+1 terms.

Thanks and sorry about the links.

 

[kwabon]

give me 2 minute.

farking latex.

oh well, will scan up solution.

win win situation.
(y)

 

[GUSSSSSSSSSSSSS]

for the first one:

ima sorry i cbb doing (a) but wat you do is you write out the area of each rectangle then sum it up:
ie: area of first rectangle = h * f(0)
area of second rectangle = h * f(h)
area of third rectangle = h * f(2h)

and then write f(h) etc as 7^h and sum them as a GP

for part (ii):
the area of the rectangles will be LESS than the area found by the DEFINITE INTEGRAL of f(x) between x=1 and x=0
so just integrate 7^x between x=1 and x=0 and put it greater than ur result in (i)

part (iii):
well tbh i cant really explain this one without the aid of a graph...but you draw the rectangles so that the area of the FIRST rectangle is now: h * f(h) .....part of the area of the rectangle is ABOVE the line
and then do exactly wat you did in part (i) to get the LHS,,,,and then since SOME of the area is above the line,,,this area will be GREATER than the definite integral
i hope that sorta made sense =S ima crap at explaining it without a graph


sorry i didn actually write solution to it....but i suck at writing maths on computer =[[[

 

[untouchablecuz]

enjoy

 

[kwabon]

wayyy to late, and waayyy to messy.
hopefully you can understand what i am doing.

hate my comp. ;-(

 

[clintmyster]

thanks guys, that helped.

Did anyone get a chance to look at the second question the one I had about about whether my teacher's solution was right?

 

[Amplifiedspeakr]

hope this helps

if you factorise the 5 outside, then you will get the GP as the (i) perhaps your teacher forgot this

 

[clintmyster]

hope this helps

if you factorise the 5 outside, then you will get the GP as the (i) perhaps your teacher forgot this

ah okay thanks heaps