Proving a property of trapezium
65964
Prove that the line joining the midpoint of parallel sides of a trapezium passes through the point of intersection of diagonals
77253
Proof of Lagrange Identity
122326
Proving $|P(A\cap B)-P(A)P(B)|\leq \frac{1}4$
104548
Geometric proof for irrationality of $\pi$
153654
How many non congruent trapeziums are possible with the side lengths from {1,3,4,5,6}
1821
Proving $f(C) \setminus f(D) \subseteq f(C \setminus D)$ and disproving equality
35236
Proof $p \vdash q \Rightarrow p$
2251
Can someone give me a hint on how to prove this?
90828
Help proving exercise on sequences in Bartle's Elements
39708
Proving $(A\le B)\vee (B\le A)$ for sets $A$ and $B$
27901
Proving $\sum\limits_{i=1}^k | \langle x,v_i \rangle \langle y,v_i\rangle| \leq \|x\|\cdot \|y\|$
134049
Showing an inequality is valid
124424
How to show that there is a deduction of $\varphi\leftrightarrow\psi$
108704
Help with proof of $|x+y| \geq |x|-|y|$
145759
formal proof from calulus
92609
How to Mathematically Prove the Bilinear Pairing Properties
116305
Proving DeMorgan's Theorem