Question

x2+x=5 then what is (x+3)3+(1/x+3)3=?​

Answer 1

Answer:

x^2 + x = 5 => (x+3)(x-2)=-1 => 1/(x+3) = 2-x Now, (x+3)^3 + (1/(x+3))^3 => (x+3)^3 + (2-x)^3 Using a^3 + b^3 ... ab= 1 =>a^3+b^3=(a+b)(a^2+b^2-1) (a+b): (x+3) +(1/(x+3 )= (x^2+6x+10)/(x+3) =(x^2+x+5x+10)/(x+3)