₦airaland Forum

Dygeasy: Smh... Psycho!

Wah name do we call him now?

I'd call him a psycho.... I admire his determination buh he's still a silly old landless farmer!

He died for nothing... Well he moved a mountain, that'd be written in gold in their book of history righ? Okay

digitalwale: How can I PM you? I tried going to your profile and clicked to send email but the page that came up only showed a prepared and uneditable message.

digitalwale: This is outstanding! Lemme have your phone number

ogugua88: [size=13pt][color=RED]Red.[/color] I'll use the $1 million to start a business and make over $100 million. Then, I'll hire 50% of the people who pressed [color=GREEN]green[/color] [/size]

digitalwale: 1000 naira GLO recharge card for anyone who can prove the below mathematical expression.

Given that Q = xyz
Prove that the CURL of GRAD Q = 0

digitalwale: 1000 naira GLO recharge card for anyone who can prove the below mathematical expression.

Given that Q = xyz
Prove that the CURL of GRAD Q = 0

Flytefalls: ^ Boy, you dey craze .

Hustle your mandem come, yu cyan reach mi!

joangirl: Ajekako

Flytefalls: Lol, don't worry. You should know Imma ride or die 24/7 for 190 . There is just something about him... BUT WHERE THE PHUCK IS HE?!?!

Flytefalls: Lol, yes . (I see that perhaps it is a dumb request but it would certainly impress me! I am part chinese.)

Flytefalls: Lol, I know what you said. But I'm not only Jamaican. If you wanna holla at me in patois, then why not in the other languages that made me

Flytefalls: I wasn't joking. Honour my ancestors

Flytefalls: Pahahaha!! . I'm not a "shotta yute" or ganj@ farmer.

Now speak Mandarin.

Flytefalls: Hahaha! Mi dey yah! Nothin nah gwan lol. Me gaan.

doubleDx: Same method, I'll do it later.

doubleDx: Nah, I graduated a few years back.

Thanks for the compliment!

Truman155: If a+b+c=8, a^2+b^2+c^2=16 and a^3+ b^3+c^3=64 find a,b, and c.

doubleDx: I have succeeded in solving one of those questions. Follow the steps carefully and you will understand. Here it goes:

x + y + z = 2 .....equation1
x^2 + y^2 + z^2 = 26 ....equation 2
x^3 + y^3 + z^3 = 38 .... equation 3

Before we proceed. We have to create an expression for x^3 + y^3 in terms of (x + y)

Using add and substraction method to factorize the polynomial x^3 + y^3 yields:

x^3 + y^3 can be expressed as : (x + y)^3 - 3xy (x + y)

Also x^2 + y^2 can be expressed as : (x + y)^2 - 2xy

Now, having created an expressing for the above.

From equation 1, (x + y) = (2 - z) ....equation 4

Substituting the expression for x^2 + y^2 in equation 2 yields :
(x + y)^2 - 2xy + z^2 = 26 .... equation 5

Substituting the expression for x^3 + y^3 in equation 3 yields:
(x + y)^3 - 3xy (x + y) + z^3 = 38 .... equation 6

Since we already know the expression for x + y = (2-z) in terms of z. We can now find an expression for xy from equation 5 so we can substitute back in equation 6 to give us the values of z.

Computing xy in terms of z, subtitute x + y = (2 - z)

(2 - z)^2 - 2xy + z^2 = 26
2xy = (2 - z)( 2 - y) - 26 + z^2
2xy = 4 - 4z + z^2 - 26 +z^2
2xy = 2z^2 - 4z - 22
:. xy = z^2 - 2z - 11

Having known the expression for xy interms of z as written above. We can now substitute both expression (i.e the for (x + y) and xy) in terms of z in equation 6. x + y = (2 - z) and xy = z^2 - 2z - 11

(x + y)^3 - 3xy (x + y) + z^3 = 38
substituting yields :
(2 - z)^3 - 3 ( z^2 - 2z - 11) (2 - z) + z^3 = 38

Expanding and collecting like terms yields:

3z^3 - 6z^2 - 33c + 36 = 0
Simplying:

z^3 - 2z^2 - 11z + 12 =0
Factorizing the polynomial gives :
(z - 1)(z^2 -z -12) = 0
(z - 1)(z - 4)(z + 3) = 0

Hence the values of z are :
z1 = 1, z2 = 4 and z3 = -3

We can now subsitute the values of z in equations 1 and 2 to evalaute x and y.

I'll be right back with the remaining solution. I hope this helps.