In: Advanced Math
8. (20 pts)
a. RSA encryption. Let n = pq = (7)(17) = 119 and e = 5 define a (very modest) RSA public key encryption. Since 25 < 119 < 2525, we can only encode one letter (two digit representation) at a time. Use the function ? = ? mod ? to encode the word MATHY into a series of five numbers that are less than n.
b. To decrypt an RSA encrypted message, we need to find d, the multiplicative inverse of e modulo (p-1)(q-1). Use Euclidian algorithm and two-pass method to determine the Bezout coefficient of e for the RSA in Part a. above. Then write down the decryption function.
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