To disprove, only one counter example is sufficient.
3. (6 points) Disprove the following: For all a, b, c E Z, if aſbc, then...
(1) Prove or disprove the following statements. (a) Let a, b and c be integers. If aſc and b|c, then (a + b)|c (b) Let a, b and c be integers. If aſb, then (ac)(bc)
a) Let z,w ∈ C, prove or disprove: Ln(z/w) = Lnz − Lnw b) Find all values in C and the principal value of j^j and ln(-3) c) Find all z ∈ C such that i. tanh z = 2 ii. e^z = 0 iii. Ln(Ln(z)) = −jπ
2. Let a,b,c E Z. Prove the following. If aſb then g.c.d(b, c) = 1 implies g.c.d(a, c) = 1.
Let a, b, c e Z with a + 0. If a|c, then there exists an integer b such that aſb and b|c.
(4 pts) Choose the true statement. Let a,b,c e Z with a #0. If a|(b + c) and a|bc, then a|(+ c´). Let a,b,c e Z with a +0. If a|(62 +c), then a|(b+c). Let a, b, ce Z with a + 0. If a|(b+c), then aſb or a|c. Let a,b,c e Z with a +0. If a|(62 +c) and a|(b+c?), then a|(+ c´). the four other possible answers are false
1. Let a, b,cE Z be positive integers. Prove or disprove each of the following (a) If b | c, then gcd(a, b) gcd(a, c). (b) If b c, then ged(a., b) < gcd(a, c)
16. (8 points) Let Z be the integers and let A - Zx Z. Define the relation R on A by (a, b) R(c, d) if and only if a c and b 3 d for all (a, b), (c, d)E A. Prove that R is a partial ordering on A that is not a total ordering.
16. (8 points) Let Z be the integers and let A - Zx Z. Define the relation R on A by (a, b)...
disprove that the given lan 4. [20 Points For each of the following languages, prove or guage is regular (a) L1www e {a,b}*} {w w E {a, b}* and no two b's in w have odd number of a's in between}. (b) L2 (c) L3 a" (d) L4 vw n = 3k, for k > 0}. a, b}*}
disprove that the given lan 4. [20 Points For each of the following languages, prove or guage is regular (a) L1www e...
6. Let A, B, and C be subsets of some universal set U. Prove or disprove each of the following: * (a) (A n B)-C = (A-C) n (B-C) (b) (AUB)-(A nB)=(A-B) U (B-A)
6. Let A, B, and C be subsets of some universal set U. Prove or disprove each of the following: * (a) (A n B)-C = (A-C) n (B-C) (b) (AUB)-(A nB)=(A-B) U (B-A)
2) Prove or disprove the following statements: (a) "If A E M5(R) has a non-real eigenvalue, then A is diagonalizable." (b) "If 2 E C" is an eigenvector of A € Mn(C) then Z is also an eigenvector of A."