







Two overlapping arcs in a square 
20140315 

Jean pose la question : I have a square with side 4 cm. There are two overlapping arcs going from vertex to diagonal vertex. The other two vertices are the center of the arcs, which are shaded. How do I find the area of the shaded arcs? The overlapping arcs when shaded resemble a long thin football
Thank you for your help. Penny Nom and Walter Whiteley lui répond. 





A problem with arc sine 
20060707 

Scott pose la question : How to prove arc sin x = arc tan( (x)/√(1x2))
Penny Nom lui répond. 





The interior angles of a right triangle 
20060520 

Greg pose la question : I am wondering if there is a way to figure out the interior angles of a right triangle if we know ONLY the side lengths, and the trick is, we CANNOT use arctangent! Leeanne Boehm and Penny Nom lui répond. 





Sectors and arcs 
20060125 

Wael pose la question : How is the area of an arc (alpha*pi*r squared/360) derived?
How is the length of an arc (alpha*pi*r/180) derived? Penny Nom lui répond. 





arcsech x 
20050210 

Monica pose la question : Prove that arcsech x = ln[(1 + (1x^{2})^{(1/2)}) / x ] Penny Nom lui répond. 





Arcs and chords 
20050109 

Aniesha pose la question : A chord of a circle is 48 centimeters long and is 10 centimeters from the center of the circle. Find the radius? Penny Nom lui répond. 





A belt around two pulleys 
20041207 

Ian pose la question : a belt is stretched around two pulleys whose centers are d units apart and whose radii are R and r respectively (obviously R+r<d). the challenge is to find the length of the belt, l as a formula in terms of R, r, and d only. Penny Nom lui répond. 





An arc of a circle 
20041205 

Ruben pose la question : i have an arc 55 inches wide, 12 inches high at the centerline of the arc. how can i determine the diameter of the circle that would correspond to the arc. Penny Nom lui répond. 





The length of an arc 
20041121 

Daryl pose la question : I am tying to find the arc length of a line 6' and the vertex of the arc 1' off of the line. that is all that is known Penny Nom lui répond. 





The radius of a circle 
20040824 

Peter pose la question : If you slice any circle with a line, and call the distance of the line between intersections the "y" length and the perpendicular length to the shorter side of the curve the "x" length, what is the resulting equation for the radius? Penny Nom lui répond. 





cot(arcsin 3/5) 
20010107 

Jason pose la question : Find value. Assume that all angles are in Quadrant 1. cot(arcsin 3/5) Harley Weston lui répond. 

