1.` z-7+7xy-xyz = ?` ` (a) (-1+xy)(-7+z) (b) (1-xy)(z+7) ` ` (c) (1+xy)(z-7) (d) (1-xy)(z-7)`

If xy + yz + zx = 1 find (x+y)/(1-xy) + (y+z)/(1-yz) + (z + x)/(1-zx) = ?

xy^(2)- yz^(2)-xy +z^(2) =_____

Solve (9xy + 7 xy + 9x ^(2)) + ( 8 + x ^(2) - xy - y ^(2) + 1).

If xy+yz+zx=1 show that (x)/(1-x^(2))+(y)/(1-y^(2))+(z)/(1-z^(2))=(4xyz)/((1-x^(2))(1-y^(2))(1-z^(2)))

If (b)/(y) + (z)/(c) = 1 and (c)/(z) + (x)/(a) = 1 , then what is (ab + xy)/(b x) equal to ?

Factorise. (i) x^2 + xy + 8x + 8y (ii) 15xy - 6x + 5y - 2 (iii) ax + bx - ay - by (iv) 15pq + 15 + 9q + 25p (v) z - 7 + 7xy - xyz

((3)/(7)z-(1)/(2))/(z-(1)/(4))-(3)/(14)=(1)/(7)