If `z(1+a)=b+i ca n da^2+b^2+c^2=1,` then `[(1+i z)//(1-i z)=`
A. `(a+i b)/(1+c)`
B. `(b-i c)/(1+a)`
C. `(a+i c)/(1+b)`
D. none of these

If z=(1+2i)/(1-(1-i)^(2)), then arg (z) equals a.0 b.(pi)/(2) c.pi d .non of these

If z=(1)/((2+3i)^(2)), then |z| is a.(1)/(13) b.(1)/(5) c.(1)/(12)d .non of these

If z=((1+i)/(1-i)), then z^(4) equals a.1b.-1c0d non of these

If a,b,c are real numbers and z is a complex number such that,a^(2)+b^(2)+c^(2)=1 and b+ic=(1+a)z then (1+iz)/(1-iz) equals.(a) (b-ic)/(1-ia) (b) (a+ib)/(1+c) (c) (1-c)/(a-ib)( d) (1+a)/(b+ic)

If A^(3)=O, then I+A+A^(2) equals I-A b.(I+A^(1))=^(-1) c.(I-A)^(-1) d.none of these

If z=(1)/((1-i)(2+3i)), then |z| is a.1 b.(1)/(sqrt(26)) c.(5)/(sqrt(26))d .non of these

If f(z)=(7-z)/(1-z^2) , where z=1+2i , then |f(z)| is (a)(|z|)/2 (b) |z| (c) 2|z| (d) none of these

The points A(z_1), B(z_2) and C(z_3) form an isosceles triangle in the Argand plane right angled at B, then (z_1-z_2)/(z_3-z_2) can be (A) 1 (B) -1 (C) -i (D) none of these

If for the matrix A ,\ A^3=I , then A^(-1)= A^2 (b) A^3 (c) A (d) none of these

Roots of the equation are (z+1)^(5)=(z-1)^(5) are (a)+-i tan((pi)/(5)),+-i tan((2 pi)/(5))(b)+-i cot((pi)/(5)),+-i cot((2 pi)/(5))(c)+-i cot((pi)/(5)),+-i tan((2 pi)/(5))(d)none of these