







A proof involving real numbers 
20100111 

Amper pose la question : Let a,b is an element of real numbers, and suppose that for every x>0 we have a is lesser than or equal to b+x.
(a) Show that a is lesser than or equal to b.
(b) Show that it does not follow that a is lesser than b.
i'm feeling bad of having no idea with this, hope i you can help me. GRACIAS!! Penny Nom lui répond. 





A radius and a tangent to a circle 
20071204 

elizabeth pose la question : show that the radius of a circle meets a tangent line to the circle in a 90 degree angle.
hint: start by assuming they are not perpendicular and at a contradiction. Penny Nom lui répond. 





Proof that any side of a triangle is less than half the perimeter. 
20070707 

Omkar pose la question : Any side of a triangle is smaller than half of its perimeter, prove this in short ? Stephen La Rocque lui répond. 





An isosceles triangle 
20050103 

Abraham pose la question : The question is,"Triangle ABC is not isosceles.Prove that if altitude BD were drawn, it would not bisect AC."My question is If an altitude is drawn wouldn\'t that mean automatically its isosceles because, In a triangle the sides opposite congruent angles(in this case the right angles)are congruent? What am I thinking wrong? Harley Weston lui répond. 





A theorem involving a trapezoid 
20040929 

Abraham pose la question : Given:Trapezoid ROSE with diagonals RS and EO intersecting at point M
Prove:Diagonals RS and EO do not bisect each other. Harley Weston lui répond. 





Contradiction in the Procedural Precedence and the Distributive property 
20030703 

Arthur pose la question : When complicated expressions exist on both sides of a fraction, and both these expressions contain like and unlike terms with "literal" coefficients, the procedural precedence suddenly gets extremely confusing and seems impossible to simplify. This seems confusing and impossible to simplify because there is a HUGE contradiction in the way Procedural Precedence and the Distributive property deal with Parentheses. The Procedure says you MUST deal with what's INSIDE the parenthesis FIRST, BEFORE dealing with ANYTHING on the outside where as the Distributive property contradicts that by saying to go ahead and ignore the Precedence and use a factor on the outside of the Parenthesis. Claude Tardif lui répond. 





Two algebra problems 
19991217 

Michael Standfest pose la question : If x+4 is a factor of 2x^{4}+kx^{3}3kx^{2}+6x40, find k and Prove that n^{2}n is even for all n, using the proof of contradiction Penny Nom lui répond. 





Root 17 is Irrational 
19990121 

John Murdock pose la question : If you could help me out with this I would appreciate it. Prove that the square root of 17 is irrational. Harley Weston lui répond. 

