If xy(x+y)=1, then $$ {1\over x^3 y^3}-{x^3-y^3}$$ is equal to-

If (27x³ – 343y³) ÷ (3x – 7y) = Ax² +By² + 7Cyx, then the value of (4A – B +5C) is:

If $$ {x+{9\over x}=6}$$  then find the value of $$ {x^{2}+{1\over x^{3}}}$$

If $$ {x+{1\over x}}=2$$ then find out the value of $${2x^2+2}\over{3x^2+5x+3}$$

If $$64^{x+1}={64\over 4^x}$$, then the value of x

If a, b are rational number and (a-1)√2+3=b√2+a, the value of (a+b) is : 

if $$x-{1\over 5},x≠0,$$ then what is the value of $${x^6+3x^3-1}\over x^6-8x^3-1$$=?

If $$ {x^2} -4x-1 $$ then the value of $$ {{x^6} -{x^4}+{x^2}-1}\over {x^3}$$ will be