Mathematics: Post your doubts here!

[Dubi Pro]

The whole thing
(x2 +x4) + (x1 + x3) = 180

\Yes so the same thing applies in the question i gave?

 

[***amd***]

doing a good job here. I was thinking that we start tutoring people. Earn paisa.. u know

buss let this bloody O level end

 

[Dubi Pro]

buss let this bloody O level end

jus a 1 mark quest bro

this question comes again and again in the histogram part! any idea HOW!

 

[***amd***]

jus a 1 mark quest bro

this question comes again and again in the histogram part! any idea HOW!

the histogram is frequency density against time (not frequency against time).
and

frequency density = frequency / time interval

and...
frequency density represented by 1 cm on y axis is 5.
time represented by 1 cm on x axis is 0.5
and thus we conclude 5 = freq./0.5
hence frequency = 5 * 0.5
freq. = 2.5
hope you got it

 

[Atharva Joshi]

Just a little help from my side

 

[Dubi Pro]

the histogram is frequency density against time (not frequency against time).
and
and...
frequency density represented by 1 cm on y axis is 5.
time represented by 1 cm on x axis is 0.5
and thus we conclude 5 = freq./0.5
hence frequency = 5 * 0.5
freq. = 2.5
hope you got it

Ah alright at the x axis how did u get 0.5?

and to conclude we can say that 1cm square means 5 block yes?

 

[Dubi Pro]

see

the histogram is frequency density against time (not frequency against time).
and
and...
frequency density represented by 1 cm on y axis is 5.
time represented by 1 cm on x axis is 0.5
and thus we conclude 5 = freq./0.5
hence frequency = 5 * 0.5
freq. = 2.5
hope you got it

see bro even i got 2.5 can u say if it makes sense?

jus like u did..

y axis 1 cm square is 5
x axis 1 cm square is 2
5/2 is 2.5

makes sense?

 

[***amd***]

Ah alright at the x axis how did u get 0.5?

and to conclude we can say that 1cm square means 5 block yes?

coz the xcale used is 2 cm = 1 unit n x axis

you dont need to state any conclusion.

see

see bro even i got 2.5 can u say if it makes sense?

jus like u did..

y axis 1 cm square is 5
x axis 1 cm square is 2
5/2 is 2.5

makes sense?

bro, i guesss u should better ask your teacher to teach you the whole of what is "frequency density".

 

[Dubi Pro]

coz the xcale used is 2 cm = 1 unit n x axis

you dont need to state any conclusion.

bro, i guesss u should better ask your teacher to teach you the whole of what is "frequency density".

Yep Shall Revice that too! thanks alot for help anyway!

 

[princess sofia]

guys! the iii part of question 2B

they told if OV IS v and OL is 2LV

what is Vector ML then? :S anyone to help?

 

[Dubi Pro]

i knw the answer can anyone here give me the proper resoning as why the angle in part b and part d are this?

Really going confused!

 

[***amd***]

i knw the answer can anyone here give me the proper resoning as why the angle in part b and part d are this?

Really going confused!

b)
you see, ABD is a triangle, and the sum of interior angles of a triangle is 180.
secondly,

the angle formed at the circumference by the diameter of the circle is 90

. I mean, angle BAD = 90.

so we say, 58 + ADB + 90 = 180
58 + ADB = 180 - 90 = 90
ADB = 90 - 58

d)
angle at the centre of circle by a chord (in this case, angle AOD) = twice the angle made by the same chord at circumference (in this case ACD)
as we know, ACD = 58
so AOD = 58 * 2 = 116

we know, OA = OD = radius of the circle. thus triangle AOD is isosceles.
so OAD = ODA = x
x + x + 116 = 180
thus x = 32

i have already said in part (b), BAD = 90
BAD = BAC + CAO + OAD
(remember, BAC = BDC!!!)
90 = 34 + CAO + 32
we get, CAO = 24.

 

[Dubi Pro]

b)
you see, ABD is a triangle, and the sum of interior angles of a triangle is 180.
secondly, . I mean, angle BAD = 90.

so we say, 58 + ADB + 90 = 180
58 + ADB = 180 - 90 = 90
ADB = 90 - 58

d)
angle at the centre of circle by a chord (in this case, angle AOD) = twice the angle made by the same chord at circumference (in this case ACD)
as we know, ACD = 58
so AOD = 58 * 2 = 116

we know, OA = OD = radius of the circle. thus triangle AOD is isosceles.
so OAD = ODA = x
x + x + 116 = 180
thus x = 32

i have already said in part (b), BAD = 90
BAD = BAC + CAO + OAD
(remember, BAC = BDC!!!)
90 = 34 + CAO + 32
we get, CAO = 24.

Right, undeerstoood very well! (Y) thanks man!

can i ask this as well only last two parts of the angle property?
for angle CBO why cant we use the cyclic quad propeerty?
whats the main thing then?

 

[Dubi Pro]

b)
you see, ABD is a triangle, and the sum of interior angles of a triangle is 180.
secondly, . I mean, angle BAD = 90.

so we say, 58 + ADB + 90 = 180
58 + ADB = 180 - 90 = 90
ADB = 90 - 58

d)
angle at the centre of circle by a chord (in this case, angle AOD) = twice the angle made by the same chord at circumference (in this case ACD)
as we know, ACD = 58
so AOD = 58 * 2 = 116

we know, OA = OD = radius of the circle. thus triangle AOD is isosceles.
so OAD = ODA = x
x + x + 116 = 180
thus x = 32

i have already said in part (b), BAD = 90
BAD = BAC + CAO + OAD
(remember, BAC = BDC!!!)
90 = 34 + CAO + 32
we get, CAO = 24.

and the EDO also 2 marks! might be something unusal also cuz angle C and ANGLE D are equal by the property : angles subtended at the same arc?

 

[***amd***]

and the EDO also 2 marks! might be something unusal also cuz angle C and ANGLE D are equal by the property : angles subtended at the same arc?

which angles are you exactly talking about?

 

[***amd***]

Right, undeerstoood very well! (Y) thanks man!

can i ask this as well only last two parts of the angle property?
for angle CBO why cant we use the cyclic quad propeerty?
whats the main thing then?

for a cyclic quad, all the vertices must touch the circumference. but, u see O is not lying on circum.
c)
C is not = D
but u see, COD = 2DEC
so DEC = 19
19 + D + 90 = 180. got it?

 

[Dubi Pro]

for a cyclic quad, all the vertices must touch the circumference. but, u see O is not lying on circum.
c)
C is not = D
but u see, COD = 2DEC
so DEC = 19
19 + D + 90 = 180. got it?

rightt! but why cant angle c and angle D be same? there is a property yea? thats they subtended by same arc

 

[***amd***]

rightt! but why cant angle c and angle D be same? there is a property yea? thats they subtended by same arc

they arent subsstended by any arc o rchord. the chord must touch the circum twice, whereas the line u are talking about touches the circum once and the 2nd it touches the center, O, not circum.

 

[Dubi Pro]

they arent subsstended by any arc o rchord. the chord must touch the circum twice, whereas the line u are talking about touches the circum once and the 2nd it touches the center, O, not circum.

ahhhh Right bro! That was the confusion thanks!

 

[Dubi Pro]

in this quest, the lAl is 32

but the problem is the matrix is in fraction. when im multiplying im getting a wrong asnswer. but when i invert the 1/32 to 32/1 and multiply the naswer is correct.

any idea why?