If a=25, b=15 , c=-10 then find the value of $$ {a^{3}+b^{3}+c^{3}-3abc\over {(a-b)^{2}+(b-c)^{2} +(c-a)^{2}}}$$

If x = a - b, y = b - c, z = c - a, then the numerical value of the algebraic expression x³ +y³ + z³ -3xyz will be 

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

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 15x² – 26x + 8 = (Ax + B) (Cx + D), where A and C are positive integers, then what is the value of (2A + B – C – 2D) ?

If a + b = 1 and a³ + b³ + 3ab = k, then the value of k is

If x = z = 225 and y = 226 then the value of : x³ + y³ + z³ – 3xyz is