Question

If 2 X + 3 Y is equal to 12 and X Y is equal to 6 find the value of 8 x cube + 27 y cube

Answer 1

ANSWER : -

1512

FORMULA :-

x cube + y cube =(x+y whole cube) - (3xy(x+y))

Answer 2

hey mate here is your answer...

(2x+3y)^3=12^3

(2x)^3+(3y)^3+3*2x*3y(2x+3y)= 1728

according to the identity that is (a+b)^3=a^3+b^3+3ab(a+b)

so,

8x^3+27y^3+108*12=1728

8x^3+27y^3+1296=1728

8x^3+27y^3=1728-1296

8x^3+27y^3=432

so your answer is 432 ...

hope it may help you