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Mathematics: Post your doubts here!

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No brother i i was asking for the last part i.e (iv) . :/
It is asking for the minimum value of dy/dx... dy/dx= 3x^2 - 8x +4
thus yu just have to find minum value of that quadratic function
Two ways to do it .. Do completing squares or just derivate it again and equate it to zero .. u shall get x substitute that x to the dy/dx equation and that will be yur anser
 
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It is asking for the minimum value of dy/dx... dy/dx= 3x^2 - 8x +4
thus yu just have to find minum value of that quadratic function
Two ways to do it .. Do completing squares or just derivate it again and equate it to zero .. u shall get x substitute that x to the dy/dx equation and that will be yur anser
hmm..okay i got it.Thanks.
 
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Can someone help me with this question?
The question is as follows:
b7m5no.png


Basically I found the area of the ABC sector and added the segments below the AB and AC lines.
This is how I went:
AB = 2r.cos(theta)
AngleBAC = 2(theta)
A of sector ABC = 1/2 x (AB)^2 x (2theta)
= 1/2 x (4r^2.cos^2theta.) x (2theta)

OA = r
A of the segments below the AC and AB lines:
2 x [ 1/2 x (OA)^2 x (2theta - sin2theta)
2r^2.theta - r^2.sin2theta

I added both and equated to half the area of the circle, i.e [ 1/2 x pie x r^2)
But couldn't reach the given result..

Can someone please give this question a shot? Would highly appreciate it.
 
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Can someone help me with this question?
The question is as follows:
b7m5no.png


Basically I found the area of the ABC sector and added the segments below the AB and AC lines.
This is how I went:
AB = 2r.cos(theta)
AngleBAC = 2(theta)
A of sector ABC = 1/2 x (AB)^2 x (2theta)
= 1/2 x (4r^2.cos^2theta.) x (2theta)

OA = r
A of the segments below the AC and AB lines:
2 x [ 1/2 x (OA)^2 x (theta - sintheta)
2r^2.theta - r^2.sin2theta

I added both and equated to half the area of the circle, i.e [ 1/2 x pie x r^2)
But couldn't reach the given result..

Can someone please give this question a shot? Would highly appreciate it.
let me give it a shot
 
Messages
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Can someone help me with this question?
The question is as follows:
b7m5no.png


Basically I found the area of the ABC sector and added the segments below the AB and AC lines.
This is how I went:
AB = 2r.cos(theta)
AngleBAC = 2(theta)
A of sector ABC = 1/2 x (AB)^2 x (2theta)
= 1/2 x (4r^2.cos^2theta.) x (2theta)

OA = r
A of the segments below the AC and AB lines:
2 x [ 1/2 x (OA)^2 x (theta - sintheta)
2r^2.theta - r^2.sin2theta

I added both and equated to half the area of the circle, i.e [ 1/2 x pie x r^2)
But couldn't reach the given result..

Can someone please give this question a shot? Would highly appreciate it.
p1 ? o_O
 
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Can someone help me with this question?
The question is as follows:
b7m5no.png


Basically I found the area of the ABC sector and added the segments below the AB and AC lines.
This is how I went:
AB = 2r.cos(theta)
AngleBAC = 2(theta)
A of sector ABC = 1/2 x (AB)^2 x (2theta)
= 1/2 x (4r^2.cos^2theta.) x (2theta)

OA = r
A of the segments below the AC and AB lines:
2 x [ 1/2 x (OA)^2 x (theta - sintheta)
2r^2.theta - r^2.sin2theta

I added both and equated to half the area of the circle, i.e [ 1/2 x pie x r^2)
But couldn't reach the given result..

Can someone please give this question a shot? Would highly appreciate it.
CIRCLE RULES ANGLE BOC IS 4THETA THATS THE TWICE OF TWO THETA
oops srry fr caps lock
 
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CIRCLE RULES ANGLE BOC IS 4THETA THATS THE TWICE OF TWO THETA
oops srry fr caps lock
Yes I know that. But Im not using angle BOC im using BAC. Using BAC to find the area of so sector includes the area of the segments above OB and OC, but using angle BOC includes the area of the segments below AC and AB which is fine but that's not the flawless answer.
 
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Yes I know that. But Im not using angle BOC im using BAC. Using BAC to find the area of so sector includes the area of the segments above OB and OC, but using angle BOC includes the area of the segments below AC and AB which is fine but that's not the flawless answer.
i think hogia mujh se
 
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see first my concept is area of shaded region = 0.5 area of circle
area of shaded region= sector area 1 +sector area 2 - area of two triangle
the unknown wud be AB we can find it by cos rule.
then we equate it to pi r^2 /2
 
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Change x to y and y to x
hence x = 5/1-3y
make y subject, you get y = x-5/3x
change y to f inverse.

Domain of f(x) is range of f inverse and vice-verse

so here domain of f(x) is >= 1 so range of f inverse would be >= 1
Range of f(x) is − 2.5 ≤ x < 0 so domain of f inverse will be − 2.5 ≤ x < 0

:)

Could you please explain the Range bit with some more detail please?
"− 2.5 ≤ x < 0"
 
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