If 0.4 m + 0.8 n = 2.2 and 0.8 m + 0.4 n = 1.4, then the value of $$ {m^2}+{n^2}$$ is equal to 

If x, y are two positive real number and  $$x^{1/3}=y^{1/4}$$, then which of the following relations is true?

If x + y + z=1, xy+yz+zx=-26 and x³ + y³+z³=151, then what will be the value of xyz?

If $$ {x^{12}+x^{3}\over {x^{6}}}=0$$ find $$ {x^{36}+{1\over x^{36}}}$$

If x + y = 1 and xy (xy – 2) = 12,then the value of x⁴ + y⁴ is:

If $$ x=\sqrt{\sqrt{5}+1\over {\sqrt{5}-1}}$$ then the value  of $$ {5x^2-5x-1}$$ will be:

If x – y + z = 15, xyz = -216 and xz – xy – yz = 18, then the value of $$ {x^3}-{y^3}+{z^3}=$$

If $$ {x^4}+{1\over{x^4}}$$ then find $$ {x^3}-{1\over{x^3}}=?$$