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right first attempt
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wrong

NTC PS03EMTH55 (27-04-2023)
Question 1. 5 7     (mod11).
i)
9
ii)
8
iii)
7
iv)
doesn’t exist

Question 2. If p =     , then ordp(8640) = 0.
i)
2
ii)
3
iii)
5
iv)
7

Question 3. A     time algorithm is considered to be the fastest algorithm.
i)
polynomial
ii)
exponential
iii)
sub-exponential
iv)
none of these

Question 4. Let G be a group and let g G be an element of order N 2. The Shanks’s algorithm solves the discrete logarithm problem gx = h in     steps.
i)
O(N log N)
ii)
O(N)
iii)
O(log N)
iv)
O(N log N)

Question 5. A Carmichael number cannot be     .
i)
composite
ii)
divisible by 5
iii)
even
iv)
a product of distinct primes

Question 6. An attack executed by an eavesdropper Even when she has full control over Alice and Bob’s communication network is called a     attack.
i)
chosen ciphertext
ii)
chosen plaintext
iii)
man-in-the-middle
iv)
known plaintext

Question 7. For an elliptic curve E : Y 2 = X3 + AX + B and points P = (x1,y1), Q = (x2,y2) on E, the slope of the tangent at the point P is given by     .
i)
3x12+A B
ii)
4A3 + 27B2
iii)
y2y1 x2x1
iv)
3x12+A 2y1

Question 8. Let E : Y 2 = X3 + X + 2 be an elliptic curve over 𝔽5. Then (1,2)+     = O.
i)
(1,3)
ii)
(1,2)
iii)
(4,0)
iv)
O