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

If 4x² + y² = 40 and xy = 6, then find the value of 2x + y.

If p³ – q³ = (p-q)[(p-q)²+xpq)] then the value of x is

If $$ {x+{1\over x}=7}$$ then $$ {x^{2}+{1\over {x^{2}}}=?}$$

if a=26 and b=22, then the value of   $${{a^3-b^3}\over {a^2-b^2}}-{3ab\over a+b}$$ is

$$ {x^{8}+4\over{x^{4}+2x^{2}+2}}$$ is equal to

If a = 7, b = 5 and c = 3, then the value of $$a^2+b^2+c^2-ab-bc-ca$$ is 

if x⁴+y⁴+x²y²=21 and x²+y²-xy=7, then what is the value of  $${x\over y}+{y\over x}=?$$