If 2x+3y=11/2 and xy=5/6, then the value of 8x^3+27y^3 is
a)671/8 b)583 c)583/4 d)187

• a) 671/8
  from, a^3+b^3 = (a+b)^3 -3ab(a+b)
  
  8x^3 + 27y^3 = ( 2x + 3y )^3 -3 * 2x * 3y ( 2x + 3y) = (11/2)^3 - 18* 5/6 *11/2 = 671/8
• 10 years agoHelpfull: Yes(6) No(1)