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I need an explanatory-approach answer to this question:
A quadrant of a circle of radius 6cm is cut away from each corner of a rectangle 25cm long and 18cm wide.Find the perimeter of the remaining figure.

Sirneij:
I need an explanatory-approach answer to this question:
A quadrant of a circle of radius 6cm is cut away from each corner of a rectangle 25cm long and 18cm wide.Find the perimeter of the remaining figure.

each quadrant of a circle is like a sector of a circle..

Perimeter of each of them = (1/4 x 2pi x r) + (2r),
since r = 6cm
perimeter of a quadrant = 3pi + 12.


the perimeter of all the four quadrants= perimeter of each x 4 = 4(3pi + 12) = 12pi + 48.

Perimeter of the rectangle = 2(length + bredth) = 2(25cm + 18cm) = 86cm


however, the perimeter of the remaining figure = 86 - (12pi + 48) = 38 - 12pi

Dejt4u,

Pls explain the approach you took in arriving at the 4cm.

Geofavor:
Dejt4u,

Pls explain the approach you took in arriving at the 4cm.

i'l do dat latr in the day.. I cant type the procedures out wit my phone and m nt wit pen nd paper now.. Pls bear wit me

dejt4u:
i'l do dat latr in the day.. I cant type the procedures out wit my phone and m nt wit pen nd paper now.. Pls bear wit me

Alright, thanks.

You did a great job at Dejt4u! Thesame explanatory approach is needed here:
1.Find The set of values of x and y which satifies the equation <i>x² - y - 1 =0</i> and <i>y-2x +2 =0</i>.
2.A canal has rectangular cross section of width 10cm and breadth 1m.If water of uniform density 1gm/cm^3 flows through it at a constant speed of 1000mm per minute, find the adjacent sea.
3.If the maximum value of y =1+hx-3x^2 is 13,find h.
4.If a circular paper disc is trimmed in such a way that its circumference is reduced in ratio 2:5,in what ratio is the surface area reduced?

Sirneij:
You did a great job at Dejt4u! Thesame explanatory approach is needed here:
1.Find The set of values of x and y which satifies the equation <i>x² - y - 1 =0</i> and <i>y-2x +2 =0</i>.
2.A canal has rectangular cross section of width 10cm and breadth 1m.If water of uniform density 1gm/cm^3 flows through it at a constant speed of 1000mm per minute, find the adjacent sea.
3.If the maximum value of y =1+hx-3x^2 is 13,find h.
4.If a circular paper disc is trimmed in such a way that its circumference is reduced in ratio 2:5,in what ratio is the surface area reduced?

i will attempt Questions 3 and 4.. Pls check questions 1 and 2 again.. It's lyk there are mistakes in those questions

Assuming log 4.4 = 1.4816 and log 7.7 = 2.0142, then the value of log 1/4 is? *Note* all logarithms are in base "e"

gurus in the house help out this question


integral 1/sin4x

gurus in the house help out with this question



integral dx/sin4x

worthing:
gurus in the house help out with this question



integral dx/sin4x

1/8ln(tan2x) + c

or. 1/4 ln(csc4x -cot4x) +C

argentofchange pls the working

Ajiaj:
Assuming log 4.4 = 1.4816 and log 7.7 = 2.0142, then the value of log 1/4 is? *Note* all logarithms are in base "e"

Where ar the math gurus here?

worthing:
argentofchange pls the working

::::::::::::::::::::Solution:::::::::::::::::


For second result,

1/sin4x =cosec4x

=> 1/4$cosecu du. (where u=4x)

on taking product & ratio with 'cosecu -cotu' ,

we get

1/4$ [cosecu (cosecu-cotu) /(cosecu-cotu)] du

=1/4 $[(cosec²u - cotu. cosecu )/(-cotu+cosecu)] du

which takes the form $f '(u) /f(u) du = ln[f(u)] + C

hence we have

1/4 In( cosec4x - cot4x) + c ......( replace. u)



for the first result

Oya come and solve o






Prove that (1+x^2y^2+y)dx + xdy =0 is exact and solve the equation

personal59:
Oya come and solve o





Prove that (1+x^2y^2+y)dx + xdy =0 is exact

here

Sirneij:
You did a great job at Dejt4u! Thesame explanatory approach is needed here:
1.Find The set of values of x and y which satifies the equation <i>x² - y - 1 =0</i> and <i>y-2x +2 =0</i>.
2.A canal has rectangular cross section of width 10cm and breadth 1m.If water of uniform density 1gm/cm^3 flows through it at a constant speed of 1000mm per minute, find the adjacent sea.
3.If the maximum value of y =1+hx-3x^2 is 13,find h.
4.If a circular paper disc is trimmed in such a way that its circumference is reduced in ratio 2:5,in what ratio is the surface area reduced?

Cross check your questions. If a circular object is trimmed, the circumference should reduce and not increase. I don't think that 2:5 is correct except if 5 represents the old circumference and 2 the new one. Kindly recheck or paste the snapshot.

Geofavor:
I too couldn't fault that working. But this textbook has the answers to be different.
I) 12cm
Ii) 30cm
Iii) 336cm^2

I think you checked the wrong answers,maybe there is a mistake in the typing cos I got exactly the same answers as what he got too.

That's just how the questions are.

naturalwaves:
Cross check your questions. If a circular object is trimmed, the circumference should reduce and not increase. I don't think that 2:5 is correct except if 5 represents the old circumference and 2 the new one. Kindly recheck or paste the snapshot.

agentofchange1:
here

It remain the solution for the equation

personal59:
It remain the solution for the equation

u said prove not solve hope u know d difference?

@personal59 ,

since the given D. E is exact,

by definition $Mdx + $Ndy =$0dx =C

thus, it follows that

$(1+x² y² + y)dx +$xdy = C

= x +1/3 x³ y² +2xy =C


that's it man .

hope u get?

agentofchange1:
@personal59 ,

since the given D. E is exact,

by definition $Mdx + $Ndy =$0dx =C

thus, it follows that

$(1+x² y² + y)dx +$xdy = C

= x +1/3 x³ y² +2xy =C


that's it man .

hope u get?

Its still dsame answer I was given bro nd I don't knw how the step by step was gotten will u pls explain better just like teaching a lay man

personal59:
Its still dsame answer I was given bro nd I don't knw how the step by step was gotten will u pls explain better just like teaching a lay man

hmm, i did nothing much here bro just a simple integration. , though there are different ways of solving exact DEs, but trust me i just used the simplest one i thought you should comprehend easily.

Pls can anyone help me with this...
A Cone with a sloping edge is 12m has a total surface area of 160piecm^2, what is it's base radius...Thanx

kidrossy:
Pls can anyone help me with this...
A Cone with a sloping edge is 12m has a total surface area of 160piecm^2, what is it's base radius...Thanx

A= πr(r+s)

where s=√(r² +h² )

s=sloping edge , h= perpendicular height ,r=base radius , A=total surface area

A=160πcm² , s= 12m = 1200cm


plug in the values and solve , guess you can finish up from there?

agentofchange1:
A= πr(r+s)

where s=√(r² +h² )

s=sloping edge , h= perpendicular height ,r=base radius , A=total surface area

A=160πcm² , s= 12m = 1200cm


plug in the values and solve , guess you can finish up from there?

Than bro I got 8...

anyone...
If the quadratic function 3x²-7x+R is a perfect square find R...anyways I got 49/12...just hoping to be correct

kidrossy:
anyone...
If the quadratic function 3x²-7x+R is a perfect square find R...anyways I got 49/12...just hoping to be correct

for a given quadratic expression to be a perfect square ,

b^2 -4ac=0

here a=3 , b=-7 c= R

thus 49 = 12R

R =49/12.


ur right

agentofchange1:
for a given quadratic expression to be a perfect square ,

b^2 -4ac=0

here a=3 , b=-7 c= R

thus 49 = 12R

R =49/12.


ur right

Exactly! Weldone bro, you're doing a great job here

integrate In(cosx)