Given that $i = \sqrt {-1}$, find the multiplicative inverse of $5 - i$.

The roots of $a{x^2} + bx + c = 0$ ,where $a \ne 0$ ,b,c

are non-real complex and

$a + c < b$ , then

If $(x^{2}-2)+(y+3)i=7+4i$  then x and y are 

The value of $(sin\frac{\pi }{8}+i\cos \frac{\pi }{8})^{8}{(sin\frac{\pi }{8}-i cos \frac{\pi }{8})^{8}}$ is -

If $a+b+c=0$ then the equation $3{ ax }^{ 2 }+2bx+c=0$ has