Prove a cancellation law for multiplication of numbers that is for 2 natural numbers b and c that if some natural number a we knew ab = ac prove b =c
48051
Proof related to natural numbers
51321
Prove that $A = B = C = D$
110944
Proving that $AB-BA=cI$ for nontrivial $c \in \mathbb{C}$
12954
Prove if $ac>bc$ and $c>0$, then $a>b$
13466
Prove that if a|b and b|c then a|c using a column proof that has steps in the first column and the reason for the step in the second column.
50266
In the following figure prove that: $AK||BC$
60122
Prove $(1+a+b)(1+b+c)(1+c+a)\ge 9(ab+bc+ca)$
101803
A\(B∩C) = (A\B) ∪ (A\C) how to prove?
109745
If $(a,k)=(b,m)=1$, prove that $(ab,km)=(a,m)(b,k)$.
47135
Prove if a = b, then f(a) = f(b) for any function f (with natural deduction)
43310
Proving $A\cap(B-C)$ is equal to $(A\cap B)-(A\cap C)$
84422
$AB=BA$, $AC=CA$ we need to show $BC=CB$
151038
How to prove (A v B), (A → C), (B → D) therefore (C v D)
29692
Proof verification: elementary Number Theory Proof of $am+bn = 1$
111003
Prove that if $A\triangle B = C\triangle B$, then $A = C$
38404
Prove $\gcd(a+b, a-b) = 1$ or $2\,$ if $\,\gcd(a,b) = 1$
81794
Prove that $(ab,cd)=(a,c)(b,d)\left(\frac{a}{(a,c)},\frac{d}{(b,d)}\right)\left(\frac{c}{(a,c)},\frac{b}{(b,d)}\right)$