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right first attempt
right
wrong

NTC PS04EMTH59 (01-05-2023)
Question 1. The number of primitive roots modulo 13 is     .
i)
1
ii)
3
iii)
4
iv)
12

Question 2. ord2(a) = ord3(a) if a =     .
i)
72
ii)
108
iii)
180
iv)
432

Question 3. The     algorithm reduced the discrete logarithm problem for elements of arbitrary order to the discrete logarithm problem for elements of prime power order.
i)
Pohlig-Hellman
ii)
Euclidean
iii)
Shanks’s
iv)
extended Euclidean

Question 4. A square root of 2 modulo 31     .
i)
is 4
ii)
is 21
iii)
is 23
iv)
doesn’t exist

Question 5. The solution of x17 2(mod43) is     .
i)
23
ii)
32
iii)
41
iv)
none of these

Question 6. In RSA, if p = 3, q = 11 are the primes and e = 7 is the encryption exponent, then the decryption exponent d =     .
i)
3
ii)
19
iii)
23
iv)
none of these

Question 7. The discriminant of the elliptic curve E : Y 2 = X3 3X + 3 is     .
i)
27
ii)
135
iii)
216
iv)
none of these

Question 8. The fastest known algorithm to solve the elliptic curve discrete logarithm problem in E(𝔽p) takes approximately     steps.
i)
p
ii)
log p
iii)
log p
iv)
O(p)