Mathematics: Post your doubts here!

[talhajohar]

Using product rule which states that ln(a) + ln(b) = ln(ab) .So ln(e) + ln(x^2) becomes ln(ex^2). Hope you understand!

 

[talhajohar]

can someone help me with these questions:
1-Three letters are selected at random from the word SCHOOL.Find the probablity that the selection:
a)does not contain the letter O
b)contains both letters O

2-In how many different ways can a football team of 11 players be photographed if there are to be two rows ,with 5 seated on the front row and 6 standing in the back row?In how many of these photographswould the captain be sitting in the centre of the front row?
thanx in adavnce

 

[saimaiftikhar92]

SOVLE THE FOLLOEING EQUATION AND GIVE YOUR ANSWER TO 3 SIGNIFICANT FIGURES:

5^2X-1=2(3^X)

 

[talhajohar]

SOVLE THE FOLLOEING EQUATION AND GIVE YOUR ANSWER TO 3 SIGNIFICANT FIGURES:

5^2X-1=2(3^X)

Can you give the link of this question. I used iteration to solve this.

 

[saimaiftikhar92]

http://www.xtremepapers.com/CIE/index.p ... _qp_33.pdf

IN HERE IT IS QUESTION NO 1


AND SECONDLY YOU HAVE TAKEN AS THE POWER OF 2X ONLY BEFORE EQUAL SIGN......INTSTEAD OF 5^2X-1


AND I THINK THE ANSWER IS NOT CORRECT!!!

 

[talhajohar]

http://www.xtremepapers.com/CIE/index.php?dir=International%20A%20And%20AS%20Level/9709%20-%20Mathematics/&file=9709_s11_qp_33.pdf

IN HERE IT IS QUESTION NO 1


AND SECONDLY YOU HAVE TAKEN AS THE POWER OF 2X ONLY BEFORE EQUAL SIGN......INTSTEAD OF 5^2X-1


AND I THINK THE ANSWER IS NOT CORRECT!!!

sorry but you should have put the parenthesis in the question. the solution is here.

 

[saimaiftikhar92]

THANKYOU......... I NEED HELP IN THIS ONE AS WELL:

(O.8)^X IS LESS THAN 0.5

 

[talhajohar]

THANKYOU......... I NEED HELP IN THIS ONE AS WELL:

(O.8)^X IS LESS THAN 0.5

what?

 

[saimaiftikhar92]

EXTREMELY SORRY ....... TYPING ERROR

THE QUESTION WAS;
SOLVE 8 ^X IS LESS THAN 0.5

 

[talhajohar]

THANKYOU......... I NEED HELP IN THIS ONE AS WELL:

(O.8)^X IS LESS THAN 0.5

the solution is here. when lg is applied on inequality and the value is less than 1 it cause flipping of the inequality sign. that is because log of numbers less than 1 is negative and hence it has the same effect on inequality as multiplying both sides by a negative number.

 

[Silent Hunter]

can someone help me with these questions:
1-Three letters are selected at random from the word SCHOOL.Find the probablity that the selection:
a)does not contain the letter O
b)contains both letters O

2-In how many different ways can a football team of 11 players be photographed if there are to be two rows ,with 5 seated on the front row and 6 standing in the back row?In how many of these photographswould the captain be sitting in the centre of the front row?
thanx in adavnce

i dont understand the answer to the part 2 ? i mean the checking you did ............

 

[saimaiftikhar92]

I HAVE POSTED SOME QUESTIONS ON ACCOUNTING FORUM ..... IF ANYONE OF YOU KNOWS THEN KINDLY HELP ME IN IT SINCE I HAVE MOCK TOMORROW

 

[talhajohar]

can someone help me with these questions:
1-Three letters are selected at random from the word SCHOOL.Find the probablity that the selection:
a)does not contain the letter O
b)contains both letters O

2-In how many different ways can a football team of 11 players be photographed if there are to be two rows ,with 5 seated on the front row and 6 standing in the back row?In how many of these photographswould the captain be sitting in the centre of the front row?
thanx in adavnce

i dont understand the answer to the part 2 ? i mean the checking you did ............

I did 11C6 to get the number of combinations with which 6 of the players are chosen for the back row. The rest are obviously going to sit in front so no need to 11C5. Then for finding total number of arrangements in the back row i found 6! and for the front row likewise found 5!. And then got their product. As the number of unique positions are 11 so 11! would give us the result. Dividing one row of 11 into two of 6 and 5 does not make a difference as the number on unique positions still remain 11.

 

[ZorroDelavega]

http://www.xtremepapers.com/CIE/Cambrid ... 2_qp_2.pdf
need a marking scheme plz anyone :unknown:

 

[abcde]

http://www.xtremepapers.com/CIE/Cambridge%20O%20Levels/4024%20-%20Mathematics/4024_s02_qp_2.pdf
need a marking scheme plz anyone :unknown:

Hi! Welcome here!
You are inquiring about an O'level exam paper whereas this is a sub-forum for 'International A and AS level'. You may post your queries here: viewtopic.php?f=25&t=5585&start=650 .Secondly, the mark scheme for this paper is unfortunately unavailable.

 

[ZorroDelavega]

ok thx anyways

 

[sksuriza]

Re: A level math question

isnt it a physics question?

 

[saimaiftikhar92]

CAN SOMEONE PLEASE SOLVE THIS ONE:

THE EQUATION OF THE CURVE IS 6X^2 - X^3. FIND THE COORDINATES OF THE TWO STATIONARY POINTS ON THE CURVE, AND DETERMINE THE NATURE OF THESE STATIONARY POINTS.
SECONDLY, STATE THE SET OF VALUES OF X FOR WHICH 6X^2 - X^3 IS A DECREASING FUNCTION OF X.
THIRDLY, THE GRADIENT AT THE POINT M ON THE CURVE IS 12 . FIND THE EQUATION OF THE TANGENT TO THE CURVE AT M.

 

[unique840]

CAN SOMEONE PLEASE SOLVE THIS ONE:

THE EQUATION OF THE CURVE IS 6X^2 - X^3. FIND THE COORDINATES OF THE TWO STATIONARY POINTS ON THE CURVE, AND DETERMINE THE NATURE OF THESE STATIONARY POINTS.
SECONDLY, STATE THE SET OF VALUES OF X FOR WHICH 6X^2 - X^3 IS A DECREASING FUNCTION OF X.
THIRDLY, THE GRADIENT AT THE POINT M ON THE CURVE IS 12 . FIND THE EQUATION OF THE TANGENT TO THE CURVE AT M.

i) stationary point is where the derivative is zero.
dy/dx = 12x - 3x^2 = 0
x (12 - 3x) = 0
x = 0 12 - 3x = 0
x = 0 x = 4
y = 6x^2 - x^3
at x = 0, y = 0
at x = 4, y = 32
coordinates are (0,0) and (4,32)

nature is determined by double derivative.
d^2y / dx^2 = 12 - 6x
12 - 6 (0) = 12
12 - 6 (4) = -12
1 is min n 1 is max

ii) i dun knw this part sorry

iii) 12x - 3x^2 = 12
3x^2 - 12x + 12 = 0
x = 2
y = 0
y - y1 = m (x - x1)
y - 0 = 12 (x - 2)
y = 12x - 24

 

[hassam]

cant find the correct anser....plz help