Sums of Differences of 2 cubes - another maths problem to solve. (1 Viewer)

[S1M0]

(x + 1)^3 + (y - 2)^3

This is doing the sums and differences of 2 cubes.

Can't get this one, getting frustrated. Damn.

Be appreciated if you could please answer and explain the method. Thanks.

 

[Forbidden.]

(x + 1)^3 + (y - 2)^3

This is doing the sums and differences of 2 cubes.

Can't get this one, getting frustrated. Damn.

Be appreciated if you could please answer and explain the method. Thanks.

a³+b³ = (a+b)(a²-ab+b²)
a³-b³ = (a-b)(a²+ab+b²)

Solve (x + 1)³ and (y - 2)³ separately, then add them together, that's how I would answer it.

 

[watatank]

General form is

a^3 + b^3 = ( a + b) ( a^2 - ab + b^2)

This isn't a really hard question in essence but its easy to make a mistake because the algebra done has to be manipulated correctly.

Let a = (x + 1)

Let b = (y - 2)

Make sure you make use of as many different grouping symbols as you can.

 

[S1M0]

Now its not as daunting, confusing yes, but no longer daunting. And its all thanks to you guys!

Thanks! I was punching the wall in frustration and trying out methods until i asked for help.

So yeah, thanks guys, as always its much appreciated!

 

[xlr8-crillz]

and the answer is??

(x + y)(x^2 - xy + y^2) + 9?