I'm trying to enter step 5: Compute d, the modular multiplicative inverse of
e (mod φ(n)).
How do I enter this in WolframAlpha?
Technically the multiplicative inverse is equal to
(function)^-1 (1/x) || x^-1
So presumably you would just enter:
(e (mod φ(n)))^-1
The modular inverse is a result of the extended gcd, it's shown as part of the
ExtendedGCD function: http://www.wolframalpha.com/input/?i=extendedgcd(17,3233). The result of your example is -1141.
Note, when you're doing homeworks (or just fiddle around), you might want to use a more comfortable tool, I'd recommend Python. The definition of the modular inverse in Python is very simple:
def inverse(x, p): inv1 = 1 inv2 = 0 while p != 1: inv1, inv2 = inv2, inv1 - inv2 * (x / p) x, p = p, x % p return inv2