Question
Question: If z = \(\frac{\sqrt{3} + i}{2}\), then (z<sup>101</sup> + i<sup>103</sup>)<sup>105</sup> is equal t...
If z = 23+i, then (z101 + i103)105 is equal to
A
z
B
z2
C
z3
D
None of these
Answer
z3
Explanation
Solution
Sol. z = 2i(1−3⥂i) = –iw
z101 + i103 = (– iw)103 + i103 = –iw2 – i = iw
(z101 + i103)105 = (iw)105 = i (w3 = 1, i4 = 1)
Also, z = – iw ¹ i, z2 = (–iw)2 = – (w2) = –w2 ¹ i
z3 = (– iw)3 = –i3w3 = i
so, (z101 + i103)105 = z3