1
NDA 2019 Paper 1
MCQ (Single Correct Answer)
+2.5
-0.83
Read the information carefully and answer the given questions.

A complex number is given by $$z = {{1 + 2i} \over {1 - {{(1 - i)}^2}}}$$.
What is the modulus of z?
A
4
B
2
C
1
D
$${1 \over 2}$$
2
NDA 2019 Paper 1
MCQ (Single Correct Answer)
+2.5
-0.83
Read the information carefully and answer the given questions.

A complex number is given by $$z = {{1 + 2i} \over {1 - {{(1 - i)}^2}}}$$.
What is the principal argument of z?
A
0
B
$${\pi \over 4}$$
C
$${\pi \over 2}$$
D
$$\pi $$
3
NDA Mathematics 14th September 2025
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language
If $\alpha =\frac{-1+\sqrt{-3}}{2}$ then what is the value of $(1+\alpha ^{19}-\alpha ^{35})^{100}-(1-3\alpha ^{25}+\alpha ^{38})^{50}? $
 
1
-2
2
-1
3
0
4
2
4
NDA Mathematics 14th September 2025
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language
If  $(\frac{1-i}{1+i})^{2m}(\frac{1+i}{1-i})^{2n}=1$where $i=\sqrt{-1}$ then what is the smallest positive value of (m - n)?
1
1
2
2
3
4
4
8