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Let B=[1 3
5 3] i.e a 2*2 matrix , if f(x)=2x^2-4x 3 , what is f(B)?

N/B the options are also in matrix form . Please solve it vividly for me thank you

Emdee590:
Let B=[1 3
5 3] i.e a 2*2 matrix , if f(x)=2x^2-4x 3 , what is f(B)?

N/B the options are also in matrix form . Please solve it vividly for me thank you

OK


check the ur f(x) d last part is it +3. or -3 ?

agentofchange1:
OK


check the ur f(x) d last part is it +3. or -3 ?

It is +3

Emdee590:
It is +3

OK here

So that is the solving and you Have just gotten it as the answer . How do I thank you and the gurus here ? Either way I remain loyal , thank you and may God almighty keep you fit so to continue solving our questions for us . That question above na 200 level question ooo and we for we class nobody fit get that question right ... Once again thank you

Abeg make una no tire for me and ma questions ooo, because it is good that I know every steps involved in any solving as ma younger ones are looking unto me for solutions to some of their mathematical problems...una no know that kind thing again ?

Emdee590:
So that is the solving and you Have just gotten it as the answer . How do I thank you and the gurus here ? Either way I remain loyal , thank you and may God almighty keep you fit so to continue solving our questions for us . That question above na 200 level question ooo and we for we class nobody fit get that question right ... Once again thank you

did you just say 200level??

Is ur school a university, Polytechnic, college of education or a monotechnic??

Your dept?? Is it science or social sciences?

If it is social science, then no problem but if otherwise, wahala dey oo

dejt4u:
did you just say 200level??

Is ur school a university, Polytechnic, college of education or a monotechnic??

Your dept?? Is it science or social sciences?

If it is social science, then no problem but if otherwise, wahala dey oo

LOL, I believe he is in social sciences!

y=(sinx)^x^3 find dy/dx

bolkay47:
y=(sinx)^x^3 find dy/dx

here

take natural logarithm of both sides

=> lny=x^3 ln(sinx)

differentiating implicitly we have ,

=> y'/y = 3x^2 ln(sinx) + x^3cosx/sinx

=> y' =dy/dx =y(3x^2ln(sinx) +x^3cotx )

or dy/dx = x^2[ xcotx + 3ln(sinx) ] * (sinx)^(x^3)

that's it man.

agentofchange1:
here

take natural logarithm of both sides

=> lny=x^3 ln(sinx)

differentiating implicitly we have ,

=> y'/y = 3x^2 ln(sinx) + x^3cosx/sinx

=> y' =dy/dx =y(3x^2ln(sinx) +x^3cotx )

or dy/dx = x^2[ xcotx + 3ln(sinx) ] * (sinx)^(x^3)

that's it man.

exactly sir... That's what I get too

doubleDx:
LOL, I believe he is in social sciences!

You are far away from the truth , it I federal uni ooo and maths department sef

Emdee590:
You are far away from the truth , it I federal uni ooo and maths department sef

200L Math department? Na wa oh, na hin that matrix problem dey give una wahala like that? But no offense, una really need to buckle-up be that oh!

Is it that most of you were pushed to Math department when you applied to study something else? Anyways, na determination na hin be the key sha!

doubleDx:
200L Math department? Na wa oh, na hin that matrix problem dey give una wahala like that? But no offense, una really need to buckle-up be that oh!

Is it that most of you were pushed to Math department when you applied to study something else? Anyways, na determination na hin be the key sha!

bros, it is very ridiculous to be teaching 200L mathematics student that concept.. Infact, it shld be in MTH101 and 3 by 3 matrix..

Your mates in other skuls are busy battling wit tensor analysis and the likes..
Not ur fault though, but the fault of those ppl that designed your school curriculum
I'm very disappointed OP..

Emdee590:
You are far away from the truth , it I federal uni ooo and maths department sef

Well , una fit yarn anything shaa . The blaim is on both sides shaa

yoji:
Pls gurus I need help with this situation:
A car of costing 1,750,000 is to b used for 3yrs after which its to b sold off at quarter d price(437,500).if it was used for 4yrs and 3mnths, hw much shud it b sold??

At 0 year the car cost 1,750,000 (0, 1,750,000)
In 3 years the car worth is 437,500 (3, 437,500)
Slope: m=y2-y1/x2-x1
437500-1750000/3-0= -1312500/3=-437500

Line of equation using point slope form

y-y1=m(x-x1)
y-1750000=-437500(x-0)
y-1750000=-437500x
y=-437500x + 1750000
y=-437500(4.3) + 1750000
y=-131,250

dejt4u:
bros, it is very ridiculous to be teaching 200L mathematics student that concept.. Infact, it shld be in MTH101 and 3 by 3 matrix..

Your mates in other skuls are busy battling wit tensor analysis and the likes..
Not ur fault though, but the fault of those ppl that designed your school curriculum
I'm very disappointed OP..

Exactly!

I was surprised myself bruv! How can a University be teaching 200 L Math students High School & UTME Mathematics? I wonder for some schools sha! Smdh...

Emdee590:
So that is the solving and you Have just gotten it as the answer . How do I thank you and the gurus here ? Either way I remain loyal , thank you and may God almighty keep you fit so to continue solving our questions for us . That question above na 200 level question ooo and we for we class nobody fit get that question right ... Once again thank you

its OK bro , to God be glory , we learn daily , put more effort , practice daily with determination , don't always rush to post questions here or give some1 else without you actually trying exhaustively & extensively to obtain valid solution . only after which still didn't get it , then you could seek for help from others
that's how you learn / develop/ improve. your mathematical prowess .

bolkay47:
exactly sir... That's what I get too

nice.

Emdee590:
So that is the solving and you Have just gotten it as the answer . How do I thank you and the gurus here ? Either way I remain loyal , thank you and may God almighty keep you fit so to continue solving our questions for us . That question above na 200 level question ooo and we for we class nobody fit get that question right ... Once again thank you

haa! are you for real?
I answered exactly this type of question in this recently concluded jamb. Just a little change in the numerical values.
200L maths? Wow. Jamb is crazy!!!

This question was one of the questions that took my time that i couldn't finish answering all the tough questions. It took me 2mins. I made sure i got the answer though

agentofchange1:
its OK bro , to God be glory , we learn daily , put more effort , practice daily with determination , don't always rush to post questions here or give some1 else without you actually trying exhaustively & extensively to obtain valid solution . only after which still didn't get it , then you could seek for help from others
that's how you learn / develop/ improve. your mathematical prowess .

Thank you sir

pls I need the solution to an integral..
Integral of (x+3)/((x^2+2x+10)^1/2) thanks

Emdee590:
Thank you sir

UWC. sir.

miniyi:
pls I need the solution to an integral..
Integral of (x+3)/((x^2+2x+10)^1/2) thanks

OK

+++++++++++++solution +++++++++++

let's consider content of the denominator

x² +2x +10

complete the square we. get

x² +2x +1-1+10

=(x+1)² +9

we now have

$(x+3)dx /√((x+1)² +3²)

set x+1=3tan¢ .........(*)

dx=3sec² ¢ d¢

thus we have

$ (x+3)/√(9(tan²¢ +1) * 3sec²¢ d¢

simplifies to

$(x+3)sec¢d¢

recall from (*),
x+1=3tan¢ , => x= 3tan¢-1

=> $(3tan¢ +2)sec¢ d¢

=> 3$sin¢ d¢ /cos² ¢ +2$sec¢ d¢

now computing using substitution ,

we get

3sec¢ +2In(sec¢ + tan¢ ) + k


where sec¢ & tan¢ = √((x+1)² +9 )/3

& (x+1)/3. respectively.

deduce & reduce further

that's it man ,


hope u get ?

benji93:
let me give you a hint,complete the triangle by joining the dip points,then by applying circle theorem you have the upper angle gives you 90 degrees,then you can use congruent shapes to find the radius of the larger circle and then the area of the square

benji93:
What is the area of the large square ?

Using the center of the figure as O, the point where the two circles meet as A & the points where the smaller circle touches the horizontal & vertical axis as C & B respectively,
OC = x, OB = y
OA = r = 6 + x = 4 + y
=> y - x = 2
AC = x + r
BC² = x² + y²
AB² = r² + y²
Using circle theorem,
AB² + BC² = AC²
r² + y² + x² + y² = (x + r)²
r² + 2y² + x² = x² + 2xr + r²
2y² = 2xr
Substitute 2 + x & 6 + x for y & r respectively into the above equation
2(2 + x)² = 2x(6 + x)
(2 + x)² = 6x + x²
4 + 4x + x² = 6x + x²
4 = 6x - 4x
x = 2
=> y = 4, r = 8
The area of the larger square = 4r²
= 4 * 8 * 8
256

agentofchange1:
OK

+++++++++++++solution +++++++++++

let's consider content of the denominator

x² +2x +10

complete the square we. get

x² +2x +1-1+10

=(x+1)² +9

we now have

$(x+3)dx /√((x+1)² +3²)

set x+1=3tan¢ .........(*)

dx=3sec² ¢ d¢

thus we have

$ (x+3)/√(9(tan²¢ +1) * 3sec²¢ d¢

simplifies to

$(x+3)sec¢d¢

recall from (*),
x+1=3tan¢ , => x= 3tan¢-1

=> $(3tan¢ +2)sec¢ d¢

=> 3$sin¢ d¢ /cos² ¢ +2$sec¢ d¢

now computing using substitution ,

we get

3sec¢ +2In(sec¢ + tan¢ ) + k


where sec¢ & tan¢ = √((x+1)² +9 )/3

& (x+1)/3. respectively.

deduce & reduce further

that's it man ,


hope u get ?

thanks

[quote author=miniyi post=31903394]thanks [/quote


Don't mention

its fun solving but not fun typing ..



its well.

Try this :::: 500=20x+22y. Find x and y

miniyi:
thanks

oo my bad, it just dawn on me , there was a mistake in the substitution

i will post the correction later . chai ..

agentofchange1:
oo my bad, it just dawn on me , there was a mistake in the substitution

i will post the correction later . chai ..

I tried it. Got 1/6ln{(x-3)/(x+4)}+c

bolkay47:
Try this :::: 500=20x+22y. Find x and y

From LHS

500 => 20(14) + 22(10)

Since LHS = RHS
Comparing LHS & RHS yields =>

20(14) + 22(10) = 20x + 22y
14 + 10 = x + y
thus =>
x = 14 and y = 10