Help in Application of integration.

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NiCeBoY

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Hello,
Can anyone check if my answer for part (a) is correct and help me out for part (b)?

Below is the question and answers :
[attachment=1:31rh2r20]ques2.JPG[/attachment:31rh2r20]
[attachment=0:31rh2r20]ans10001.JPG[/attachment:31rh2r20]
Thank you very much..
 

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That L in the formula looks like a 1.

I get \(\displaystyle y=\frac{Wx^{2}(3L-2x)}{18I}+C_{1}x+C_{2}\)
 
yeah i know it looks like "1" but i did confirm and its "L".

So bro where is my mistake? i can;t find it...
can i have your workings please?

thanks.
 
NiCeBoY said:
Hello,
Can anyone check if my answer for part (a) is correct and help me out for part (b)?

Below is the question and answers :
[attachment=1:1xya065u]ques2.JPG[/attachment:1xya065u]
[attachment=0:1xya065u]ans10001.JPG[/attachment:1xya065u]
Thank you very much..
Click to expand...

Your work is correct.

For part (b) -what have you been taught about finding min/max of a function?
 
but how galactus got a different answer for y?

yes i need to find minimum and maximum..
how do i find this? and under what conditions?

is it x=0 when y = max?


Thanks
 
I have to be honest. I did not work this all out by and this morning. I ran it through my Voyage 200. That is what it gave me.

I was just not up to crunching those numbers this morning. Sorry. But, SK says it is good. That's good enough for me.
 
NiCeBoY said:
but how galactus got a different answer for y?

yes i need to find minimum and maximum..

If you are given a function f(x) - what is the condition for it's extremum?

f'(x) = 0

for maximum f"(x) < 0

for minimum f"(x) > 0

In deciding maximum or minimum - consider the sign of "y" (deflection).

This is first semester calculus knowledge.

is it x=0 when y = max? - may be - prove it or disprove it.


Thanks
Click to expand...
 
yes because in the diagram i can see..
if the point p will be in the middle...

i think the deflection should be a max...


so, am i right?

thx
 
NiCeBoY said:
yes because in the diagram i can see..
if the point p will be in the middle...

i think the deflection should be a max...


so, am i right?

thx
Click to expand...

This is a question of mathematics - so answer with mathematical reason. Diagrams can be misleading - sometimes intentionally.
 
mate,
i am really lost..
sorry...

if i let dy/dx = 0 ? i got more than 1 unknown.. so i can't find X?


sorry i reallyt need a solution as quickly as possible.. before tomorrow ifpossible..
sorry aboutt hat..
thx.
 
NiCeBoY said:
mate,
i am really lost..
sorry...

if i let dy/dx = 0 ? i got more than 1 unknown.. so i can't find X?


sorry i reallyt need a solution as quickly as possible.. before tomorrow ifpossible..
sorry aboutt hat..
thx.
Click to expand...

It is already to-morrow of yesterday ...

Anyway what did you get for dy/dx (according to the work you have done) - how in the heaven you are getting more than 1 unknown?

Tell us first what did you get for dy/dx?
 
it is on the image i scanned... on the fourth line.
sorry i don't know how to write it here.....


or else i need to rescan...
 
NiCeBoY said:
it is on the image i scanned... on the fourth line.
sorry i don't know how to write it here.....


or else i need to rescan...
Click to expand...

Okay now that you found the equation - set it to zero and solve for 'x'.

if i let dy/dx = 0 ? i got more than 1 unknown..
Click to expand...

Exactly where are you finding more than one unknown "variables" - what are those?
 
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