Mathematics: Post your doubts here!

[Munk Bro]

heyy guys, does anyone whether there is any pattern for AS level P1 papers n the past years... I'm doing P12... Please help me out if anyone knows.. please....

 

[Taiyaba]

Help!!!
Find the sum of the A.P. -7-3+1+.... From the seventh to the thirtieth term inclusive.

 

[aloha]

can anyone differentiate ths xy(x+y) plzz???

 

[hussamh10]

Help!!!
Find the sum of the A.P. -7-3+1+.... From the seventh to the thirtieth term inclusive.

seventh term=a+6d
=-7+6(4)
=17
13th term=a+12d
=-7+12(4)
=41

Number tems bw 7 &13=6
sum of Ap=6/2(41+17)
=174
Hope iam right not 100% sure

 

[hussamh10]

can anyone differentiate ths xy(x+y) plzz???

p3?

 

[Taiyaba]

seventh term=a+6d
=-7+6(4)
=17
13th term=a+12d
=-7+12(4)
=41

Number tems bw 7 &13=6
sum of Ap=6/2(41+17)
=174
Hope iam right not 100% sure

The sum shud b 1512 :/

 

[Dhaval Shah]

seventh term=a+6d
=-7+6(4)
=17
13th term=a+12d
=-7+12(4)
=41

Number tems bw 7 &13=6
sum of Ap=6/2(41+17)
=174
Hope iam right not 100% sure

Your working is right, but the Number of terms between 7 & 13 should be 7, not 6. If you use that the sum = 203 which i think is correct

The sum shud b 1512 :/

Are you sure, i doubt it. Like even if you do it without using a formula (getting all the terms up to 13 and then adding from the 7th to the 13th) you won't get that answer :/

 

[Tkp]

can sme1 help me with the cosine curves in as.like i have problms in this equation 3-4cosx.

 

[hussamh10]

Your working is right, but the Number of terms between 7 & 13 should be 7, not 6. If you use that the sum = 203 which i think is correct


Are you sure, i doubt it. Like even if you do it without using a formula (getting all the terms up to 13 and then adding from the 7th to the 13th) you won't get that answer :/

sorry my mistake i dont get how the sum be so big if u do it widout formula it doesnt come that big...

 

[elbeyon]

whitecorp can you or someone else please explain me the M/J 2012 Paper 11 Q. no 7 b) i). Sorry no links to the papers because they are not yet uploaded in the Xtremepapers.

 

[askha]

IGCSE Maths algebra 1 Page 77 Q 19
The numerator of a fraction is 1 less than the denominator .When both numerator and denomerator are increased by 2 , the fraction is increased by 1/12.Find the original fraction .

 

[Dhaval Shah]

sorry my mistake i dont get how the sum be so big if u do it widout formula it doesnt come that big...

haha no need to say sorry! but i agree no way the sum is thaaaat big!

 

[Dhaval Shah]

whitecorp can you or someone else please explain me the M/J 2012 Paper 11 Q. no 7 b) i). Sorry no links to the papers because they are not yet uploaded in the Xtremepapers.

I remember doing this question, and getting it wrong lol. Convergent means like the GP is going to a number but it never actually gets to that number, like you know when r of the GP is less than 1 and you have to find the sum to infinity, thats the number that it approaches but it will never get to that number! So basically you will say ((Second Term of GP)/(First Term of GP)) < 1 . Then you solve that equation that you get...

 

[hussamh10]

can sme1 help me with the cosine curves in as.like i have problms in this equation 3-4cosx.

AcosBx+c
A=amplitude
B=frequency
C=starting line (normally we start the curve frm zero but when C is their we start it in ur case from 3)

 

[hussamh10]

I remember doing this question, and getting it wrong lol. Convergent means like the GP is going to a number but it never actually gets to that number, like you know when r of the GP is less than 1 and you have to find the sum to infinity, thats the number that it approaches but it will never get to that number! So basically you will say ((Second Term of GP)/(First Term of GP)) < 1 . Then you solve that equation that you get...

I remember doing this question, and getting it wrong lol. Convergent means like the GP is going to a number but it never actually gets to that number, like you know when r of the GP is less than 1 and you have to find the sum to infinity, thats the number that it approaches but it will never get to that number! So basically you will say ((Second Term of GP)/(First Term of GP)) < 1 . Then you solve that equation that you get...

how we solve tan^2???can usolve it
http://olevel.sourceforge.net/papers/9709/9709_s12_qp_11.pdf

 

[Dhaval Shah]

how we solve tan^2???can usolve it
http://olevel.sourceforge.net/papers/9709/9709_s12_qp_11.pdf

Its simple! Ok, the equation that you form will be (tan^2x/3) < 1, then you take 3 to the other side making it tan^2x < 3, then you square root both sides making it tanx < (square root) 3. Then using precise angles (not exactly sure what its called) you should know that tan inverse (square root) 3 is 60 degrees, or (pie)/3. You get it? So x < ((pie)/3)

 

[hussamh10]

can sme1 help me with the cosine curves in as.like i have problms in this equation 3-4cosx.

 

[hussamh10]

Its simple! Ok, the equation that you form will be (tan^2x/3) < 1, then you take 3 to the other side making it tan^2x < 3, then you square root both sides making it tanx < (square root) 3. Then using precise angles (not exactly sure what its called) you should know that tan inverse (square root) 3 is 60 degrees, or (pie)/3. You get it? So x < ((pie)/3)

yeah Thanx man i get ...

 

[Farru]

i hv a ques,
its ques no 2 , nov 2011, var 11.
pls ppl tel me, tht how cn we find out tht the gradient is neg. :/
i hv seen da mark scheme but its really brief.
rep asap!

 

[leadingguy]

i hv a ques,
its ques no 2 , nov 2011, var 11.
pls ppl tel me, tht how cn we find out tht the gradient is neg. :/
i hv seen da mark scheme but its really brief.
rep asap!

can u please post the link??