ADMATHS P1 DISCUSSION!!

[Daneyal007]

there were 4 solutions.
4intersections. 2 on the x axis 2 on the curve

 

[Hamza]

yup 4 solutions because there were two intersections...Allah ka shukar hai paper went gr8... btw selections walay part ke kya answers the??

 

[alixx]

hey guys how many marks were for q4?
I just wrote y in terms of x not y^2 in terms of sec^2. my gradient was -2 how many marks will i loose?.
and secondly can anyone remind me what q4 second part whos ans was 5/6 .

 

[OakMoon!]

Find the value of cosx..

 

[haris_93]

did any do the 12 either question????what were the x coordinates???and the area under the curve??....and how many marks were of the period and amplitude ques.???

 

[rfuzzy]

was it y^2 against sec^x or y^2 against secx
and answerof cos x was .833...rite!!

 

[Marie k]

Thank GOD!!!...and thanks 4 da ans

 

[haris_93]

was it y^2 against sec^x or y^2 against secx
and answerof cos x was .833...rite!!

i guess it was y^2 against secx...

 

[Bloodlines]

attention plz!!!!!.every body has made a mistake in drawing the graph in p1 and determining the number of solutions.Number of solutions were zero.if still all of u disagree then must consult add maths key points TRIGNOMETRY chapter

 

[NoMI]

wah einstein.....ahahahahaha..........i think u need a check

 

[Bloodlines]

tu ne key points study kiay thay acha mujhe bta how you got two solutions

 

[anzaar]

the no of solutions for cosx and 1+cos2x would be 4.
cheers.

 

[anzaar]

4 solutions. using trigonometry

 

[anzaar]

there is no mark scheme available .
however i will post the solution.
Anzaar from Isd.

 

[anzaar]

here it comes

 

[NoMI]

o bhai.....answer was 4.........u will see when Mark scheme will come

 

[anzaar]

Dear
Here is the trigonometry solution of the question
cos(x)=1+cos(2x)

cos(x)=1+2cos^2(x)-1 ; cos^2(x) means cos square x
cos(x)=2cos^2(x)
cos(x){2cos(x)-1)}=0
cos(x)=0 or 2cos(x)-1=0
x= 90,270 cos(x)=1/2
x=30,330
if range is 0-180 then two solutions
if range is 0-360 then four solutions
hoping this will satisfy you.
anzaar
regards.

 

[NoMI]

nd range was 0 - 360..........
so im right