Mathematics: Post your doubts here!

[whitecorp]

if in the same question..they asked fr the mod of z where arg(z) takes its greatest value..then how do v solve it sir?

In that case we shall consider two right-angled triangles to make the necessary calculations:



Hope this helps. Peace.

Edit: My bad, I read your question wrongly as asking to find arg(z) min. Will show you the workings for |z| when arg(z) is a maximum shortly.

 

[whitecorp]

Here are the workings for finding |z| when arg(z) is a maximum:



Hope this helps. Peace.

 

[shanky631]

Need help anyone
parthrocks
whitecorp

 

[shanky631]

 

[junyl93]

Anybody can help me with ques 3. I don't know how to do the showing part...

 

[bamteck]

Cheer up, here are the workings:



Hope it helps. Peace.

Thank you loads Sir !
I was not able to simplify it further !

 

[Mattman]

http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_w09_qp_31.pdf

7 iv please. thanks in advance.

 

[Kirabo Takirambudde]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w09_qp_31.pdf

7 iv please. thanks in advance.

Here u go dude

 

[Kirabo Takirambudde]

Anybody can help me with ques 3. I don't know how to do the showing part...

Here dudee

 

[Kirabo Takirambudde]

Hello sir for iteration!!a doubt in my mind!!
Do we take the initial value as average suppose if the root lies between 1
6<x<9 then do we do (6+9)/2 and take 7.5 as initial value or just take 6 the starting value as initial value !!!
plz its uregent and many of my friends also have this doubt plz help sir

For iteration would can literally use any value that you want, its just that if you use a number like 100000, it will LITERALLY take you FOREVER to find the root, but if you take a number half way between 6 and 9 ---> 7.5, then you'll most likely get the root very quickly

 

[Kirabo Takirambudde]

Guys need some help with these 2 things!!!!

put the into a form that can be integrated:

4(cos3x)^2

&

Find the least value of N in this equation
N = e^50ksin(0.02t) + ln125

 

[bamteck]

http://www.xtremepapers.com/papers/...AS Level/Mathematics (9709)/9709_w05_qp_3.pdf

Help needed for no. 7 (i)(ii) (iii) & no. 10 please

 

[xyz!]

Here are the workings for finding |z| when arg(z) is a maximum:



Hope this helps. Peace.

hi..thnk u so much! dat was really very helpful!

 

[whitecorp]

hi..thnk u so much! dat was really very helpful!

No problem, am glad it helped. Peace.

 

[whitecorp]

Guys need some help with these 2 things!!!!

put the into a form that can be integrated:

4(cos3x)^2

&

Find the least value of N in this equation
N = e^50ksin(0.02t) + ln125

For the former, you can rewrite 4(cos3x)^2 as 4 [ (cos6x+1)/2 ] = 2 cos6x +2
(Note this is achieved through the cosine double angle formula)

For the latter, is k a constant or variable?

Peace.

 

[john10]

For the former, you can rewrite 4(cos3x)^2 as 4 [ (cos6x+1)/2 ] = 2 cos6x +2
(Note this is achieved through the cosine double angle formula)

For the latter, is k a constant or variable?

Peace.

Sir, can u plz help me.

 

[Kirabo Takirambudde]

For the former, you can rewrite 4(cos3x)^2 as 4 [ (cos6x+1)/2 ] = 2 cos6x +2
(Note this is achieved through the cosine double angle formula)

For the latter, is k a constant or variable?

Peace.

Thanks 2 the first 1, as for the second one, forgot 2 say that k=0.01

By the way, where do u get the solutions that you have been posting from?

 

[whitecorp]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w05_qp_3.pdf

Help needed for no. 7 (i)(ii) (iii) & no. 10 please

There you, Q7:



Solutions for Q10 coming soon. Hope this helps. Peace.

 

[whitecorp]

Thanks 2 the first 1, as for the second one, forgot 2 say that k=0.01

By the way, where do u get the solutions that you have been posting from?

I post them right out of my head.

 

[whitecorp]

Thanks 2 the first 1, as for the second one, forgot 2 say that k=0.01

By the way, where do u get the solutions that you have been posting from?

For N = e^50ksin(0.02t) + ln125 , recognising that sin (0.02t) will reside between -1 and +1 inclusive, we can surmise that
minimum value of sin (0.02t) will be exactly = -1.

Hence, minimum value of N = e^50 * (0.01)(-1) +ln 125
= -5.185 * 10^(19) (shown)

Hope this helps. Peace.