x-y=3 then x^3-y^3-9xy =?
There are infinitely MANY solutions to this problem, as long as the difference between x and y=3, then the answer is ALWAYS the same=27. If x=10, y=7, then the answer is 27. This remains true for any positive values of x,y separated by 3.
+118696 Thanks Guest :))
x-y=3 then x^3-y^3-9xy =?
This is fascinating. Look at this weird graph!
https://www.desmos.com/calculator/dbawqgablq
Now for the algebra.
x-y=3
so
y=x-3
Find what x^3-y^3-9xy =
x3−y3−9xy=x3−(x−3)3−9∗x(x−3)=x3−[x3−3(x2∗3)+3(x∗32)−33]−9x(x−3)=x3−[x3−9x2+27x−27]−9x2+27x=x3−x3+9x2−27x+27−9x2+27x=9x2−27x+27−9x2+27x=27
Cool!
