If a and b are the roots of the equation 2x^2 - 3x – 2 = 0. Find the value of (a^3+b^3 ) without finding the roots of the equation.
a) 8/3 b) 64/3 c) 63/8 d) 16

• its 63/8 and the roots are 2 and -1/2
• 12 years agoHelpfull: Yes(5) No(1)
• (a^3 + b^3) = (a + b)(a^2 - ab + b^2)
  = (a + b)((a+b)^2-3ab)
  
  a+b=3/2
  ab=1
  
  (a^3 + b^3)=3/2+(9/4-3)
  =3/2-3/4=3/4
  
• 12 years agoHelpfull: Yes(5) No(5)
• a^3+b^3=(a+b)(a^2+b^2+ab)
  =>(a+b)((a2+b2)-2ab+ab)
  & by equation
  a+b=-3/2
  ab=2/2
  put the value
• 12 years agoHelpfull: Yes(1) No(3)